Watch Haley and Levi Walker—aged 13 and 10—as they embrace the daily challenges of life, school, play, projects and partnerships—and you’ll see a couple of typical tree-climbing, beach-combing, dinosaur-digging, rock-climbing, snake-charming, adventure-loving kids. But for these busy siblings, their adventure includes a subliminal pioneering aspect, as well: they were born with an extremely rare neurological condition known as Hereditary Sensory and Autonomic Neuropathy, Type 6, and they’re blazing trails into this new territory every day, aided by colorful ankle-foot orthoses (AFOs) that keep them happily on the move.
Only a handful of families have had medical reporting done on this condition, so there are still many unknowns, explains Tiffany Walker, Haley and Levi’s mother, who has been working to learn more since the day Haley was born.
The onset of the condition is at birth, and although Haley seemingly was born healthy, Tiffany soon noticed hypotonia, or low muscle tone, that delayed Haley’s arrival at her gross motor milestones.
“She was very late to roll over and to sit up. I don’t think she started crawling until she was a year old, and she didn’t start walking until a few months after she turned two.”
These troubling signals weren’t ignored; Haley received physical therapy before she was a year old, but once she began walking, therapy was ended. At this point, a geneticist and a neurologist were consulted, but their evaluations and tests revealed primarily normal results, and a diagnosis remained elusive.
In Pursuit of a Diagnosis
“As parent, you know when something’s not right,” Tiffany says, recalling her frustration. “Haley’s pediatrician agreed, but there was no explanation, and no name for what we saw.”
Without a diagnosis, it was difficult to know what, if any, treatment or accommodation might be helpful—relying on a mother’s instincts and common sense seemed to be the only early option.
Eventually, Haley began to catch up to her peers—always slightly behind, but by the time she entered kindergarten, her petite size seemed to be all that distinguished her from her classmates.
Meanwhile, her brother Levi had arrived when Haley was three years old. Tiffany recalls that he met most of his milestones on time, with just a slight delay in his walking–at about 18 months.
Both Haley and Levi went to a small, home-based day care facility, where comparisons with the physical progress of their peers were less apparent. So it wasn’t until Levi’s kindergarten teacher asked Tiffany if Levi had a problem with his hips that concerns regarding possible mobility challenges arose for him, as well.
Previously, Levi’s running gait variance had been dismissed as intentionally ‘silly’—typical of his character as a playful jokester who loves to make people laugh; but once his mother’s focus was drawn to it, she recognized other clues.
“Then things started to make sense,” she recalls. “It took him longer to navigate the campus and he had a harder time keeping up with his friends. I was so thankful that the teacher brought this to my attention!”
By then, Haley had also begun attracting attention. A minor injury to her left foot had appeared to be the cause when she first started walking on the side of her foot; and although she had seen a pediatric orthopedist when the habit persisted, “she didn’t really identify any major problem, and thought it had to do with her growth,” Tiffany remembers.
But Haley’s third grade teacher, experienced in working with special needs children, recognized the troubling indicators, and encouraged Tiffany to continue to pursue her search for answers and additional opinions.
Levi was also exhibiting new symptoms with stance control, so both children began seeing a neurologist and underwent testing that was again, largely normal. They were eventually referred back to Dr. Patricia Wheeler, MD, the medical geneticist who had seen Haley when she was two years old, and who then ordered the Whole Exome Sequence Analysis which resulted in their diagnosis of Hereditary Sensory and Autonomic Neuropathy, Type 6, when Haley was 10 and Levi was 7.
We will be eternally grateful that she was willing to order one of the most extensive genetic tests that I know of,” says Tiffany, “in order to help give our family some answers. When they were younger, one of the hardest things for us was not having a diagnosis. Their condition is progressive, so there’s all that anxiety of worrying and wondering: ‘Are they doing okay? Are we doing the right thing?’”
Even with a diagnosis, however, many challenges remain, since the condition is so rare, and relatively little is known about it.
Living and Learning
“The condition affects the kids’ mobility; it also affects their fine motor function,” Tiffany explains. “They have adapted well, but still need help with everyday things. They both have muscle atrophy, which has caused significant muscle loss, especially in their legs and hands. The condition is progressive and can affect multiple systems, such as the cardiovascular, respiratory, and gastrointestinal systems.”
“I continue to try to follow any ongoing research,” she notes, recognizing that the more they learn, the better prepared they are to anticipate and address needs for changes as they arise.
Two months before they received their diagnosis, Tiffany made the decision to start home-schooling the kids, since they were having a hard time keeping up with the physical demands of school. Haley was in the 5th grade, attending classes on the second floor of the building, and by the end of the day, she was exhausted from the physical effort of just navigating the campus.
When the diagnosis arrived, the neurologists ran some additional tests, and Tiffany was relieved to finally be able to get both Haley and Levi into needed orthotic devices, as Levi had developed foot drop, and Haley was walking on the sides of both of her feet.
“Unfortunately,” Tiffany remembers, “the first set of braces just did not work for either of them. Levi’s were really bulky and heavy; he couldn’t wear them all day. And Haley’s were so uncomfortable that she could only tolerate them for about an hour at a time—not even long enough to go to church or a movie or outing. By the time we got there and sat down, we’d have to walk out and take off her braces!”
A second orthotist and a second set of braces “worked better,” Tiffany says, “but still we weren’t getting the type of individual high-quality care we ended up getting with Lawall.”
Their geneticist and pediatrician both advised the Walkers, who live in Casselberry, Florida, to consult pediatric neurologist Richard Finkel, M.D., a spinal muscular atrophy specialist and then Chief of Neurology at Nemours Children’s Hospital in Orlando, since Haley and Levi’s condition is so rare. (Dr. Finkel has since joined St. Jude Children’s Research Hospital in Memphis to lead their new Center for Experimental Neurotherapeutics.).
During their visit with Dr. Finkel and his physical therapist, they were introduced to Lawall’s Clinical Director in Nemours Children’s Hospital, Ruben Barraza, CPO, and an appointment to create new and more appropriate orthoses for Haley and Levi was quickly scheduled.
“For most families, like us, this is new territory.” Tiffany reflects. “By the time we saw the second orthotist, the orthoses were better than the first, but we still didn’t realize there was anything better. There are ways to get your kiddos into orthoses that are comfortable and do help; I felt so grateful that Dr.Finkel and his team pointed us in the direction of Lawall and Ruben!”
Making Orthoses Work
Barraza recalls his initial work with the Walker children in 2018, when Levi was 8 years old and Haley was 10.
Although they share the same rare diagnosis, individually they present quite differently, he explains. And although the condition is rare, its characteristics are similar to Charcot-Marie-Tooth disease, also known as hereditary motor and sensory neuropathy, which has been successfully managed with supportive therapy.
Barraza initially created ankle-foot orthoses (AFOs) to treat Levi’s equinovalgus condition, which involved eversion of the ankle, collapsing of the arch, and foot drop.
“In 2020, when we saw changes in his condition that included a very strong hyperextension of his knees, we started treating the knee extension as well. One of his issues was an inability to balance when standing still; he had to start shuffling and could not remain stationary without support. The braces allow him to stand without having to move.
“The braces are going to help him in providing alignment to the leg; they will control the hyperextension of the knee, the valgus of the ankle or pronation of the foot. In general,” he concludes, “they’re able to provide more support, so it’s safer to be able to stand and walk; there’s less chance of him falling. They will also reduce the amount of energy that he has to use to walk.”
One of the challenges in creating the AFO’s that now suit Levi so well, was reducing their bulk, creating low profile ankle joints, and especially achieving the precise balance for safety and stability by using an adjustable plantarflexion stop when setting the dorsiflexion angle of the brace to address the hyperextension issue.
“When we push too far forward to control the hyperextension of the knee—sometimes it’s not safe,” he warns. “They feel like they’re going to fall. That little bit of adjustment makes a big difference in Levi’s safety and confidence in walking.
“Levi is just a very fun kid to work with,” Barraza adds. “He has a super-outgoing personality, he is a joker! And he loves video games—especially Roblox. I don’t think there are any limitations on him—he’s just a normal boy.”
Haley, he reflects, is more reserved and quiet, but was excited and animated at the prospect of sharing her story with others to help and encourage them through their own mobility issues.
“She told me that she wanted other kids to be able to wear braces without being worried that somebody might be looking at them with their braces; she thought telling her story might make it easier for them to wear AFO’s,” he remembers.
Tiffany also credits Haley as the motivator for this story, for the same selfless reason. “Haley loves animals, loves science, and she has said for a long time that she wants to be either a vet or a doctor. She wants to help people. It’s funny because she’s so petite and small, but she will step up to advocate for others—it’s kind of amazing!” her mother reflects.
“No matter where she is, Haley loves to help. She is always thinking of others, and uses her creative crafting skills to make gifts for friends and family. She enjoys sharing about her condition and other helpful experiences she’s had.”
Haley was 10 when Barraza first met her–struggling with braces that were too uncomfortable to tolerate.
“The biggest issue for her,” he remembers, “was that she was never able to wear her braces. They helped, but only to a limited extent, because she wasn’t comfortable with them and couldn’t wear them long enough to do much good. They were just not made properly for the condition that she had or the way she presented—in a varus position with a really high arch, walking on the lateral portion of her foot. She had an Achilles contracture, so her ankle does not bend enough to allow her foot to rest flat on the floor.”
Re-creating a normal 90-degree ankle bend by wearing the solid-ankle AFO he created for her couldn’t be done in one drastic step, Barraza explained. He started, instead, with a less extreme angle, supporting and elevating her heel with a ½” wedge from the heel to the ball of her foot. During her most recent visit, he was able to reduce the wedge to ¼”—which allows him to reduce the overall size and bulk of her braces, as well.
“We have been working for three years now, and we’re slowly getting her there,” he observes. “Her Achilles tendon has begun to gradually stretch into the proper position and she is now able to comfortably wear her braces all day. The huge calluses that had formed to protect the lateral portion of her foot are nearly gone, now that the walking pressure on that area has been removed.
“Without braces, her gait pattern was unsteady, she walked on the lateral portion of her foot, and expended a lot more energy; but the braces provide stability—and confidence,” he concludes.
Tiffany agrees. “One of the biggest things about having AFO’s that fit her gives Haley confidence—and she can participate with her friends. Granted, she’s still going to be slower, and there are still things that she can’t do—but they allow her to be herself—and it’s just such a blessing that I can’t even describe the difference it’s made in the lives of my kiddos!
“Three years ago for Halloween, I was carrying my ten-year-old, because she could only walk so far without her braces; today, both of them are happily back in school, now attending Advance Learning Academy in Maitland (Florida), where the principal, the entire staff, the kids—are all just amazing!”
A Difference in Action
Given the opportunity to develop their potential, and aided by the Gardiner Scholarship for special needs children, both kids are on the honor roll and really thriving, Tiffany reports.
Levi the extrovert especially enjoys making waves with his AFO, she finds: “He is just goofy, silly, loves to make people laugh! He likes to create his own comics and invent games to play with his friends. Now, having the right AFO, he’s able to keep his friends actively entertained at recess—his favorite subject, he claims! His teacher says that Levi is usually the one leading the other kids—and if he didn’t have AFO’s that worked for him, he wouldn’t be doing that; he wouldn’t be able to participate with the other kids.”
It’s no longer a struggle to get the kids to don their braces and leave them on all day, she reports. “The all-day wearability has been such a blessing for them, and makes their daily activities so much easier. Now they put them on before school and don’t take them off until it’s bedtime. My husband even refers to the kids’ braces as their ‘legs’ when he suggests that they ‘Put on your legs and get ready to go!’”
Haley, at 13, is small for her age, but “definitely a teenager!” emphasizes her mother. She enjoys crafts, hanging out with her friends, loves writing, and ‘absolutely’ loves science. A focused and persistent researcher, she devotes hours on end to learning more about any new discovery that interests her.
Those interests include natural science; she has adopted and studied some unusual pet choices for such a petite, fairy-like child: not only is she an expert on rabbits like her own Bun Bun, but her up-close knowledge of reptiles rests on her experiences with a snake, a leopard gecko, and, currently, a bearded dragon.
Further evidence that her pixie-ish exterior conceals a surprising core of toughness: Tiffany reveals that one of Haley’s favorite games at school is touch football, where she has carried her team to victory by making the winning touchdown!
Levi’s goals involve helping people in different ways; his contagious smile is part of a kind-hearted gift for spreading happiness by making others laugh, and by using his boundless imagination to create comics, stories, and artistic renderings of his favorite video game characters. His carefree disposition is blended with the soul of a mathematician and practical problem-solver who frequently offers financial advice to his mom—“and sometimes charges a small fee for it!” she laughs.
Levi will play video games with his friends, his dad, or his older brother for as long as he’s allowed, but he always has time for his best friend Trudy—a lovable Border Collie-Lab mix, with Scooter the cat in a close second place.
“He dreams of being a famous YouTuber because, he claims, it’s a good way to make money! —and since he excels at anything that involves math,” says Tiffany, “he’s probably right!”
Florida is filled with outdoor entertainment options for field trips and family outings.
Home-schooling lessons and field trips take them to the Orlando Science Center, the Melbourne Zoo, local parks, and even a nearby spectator’s viewpoint of the Kennedy Space Center, where they witnessed an exciting rocket launch.
Haley and Levi spent time at the beach during their spring break, and they love to swim in their home pool on warm afternoons and early evenings—often accompanied by four-legged lifeguard Trudy.
At home, Haley likes to help cook, and is famous for her scrambled eggs. She enjoys watching sports with her Dad, while Levi enjoys board games and organizes family game nights.
Visits from Styles, their adored big brother, who is currently serving in the U.S. Army, are occasions for celebration, and the family makes frequent trips to Virginia to visit other relatives there, as well.
“We are very aware that we are blessed,” reflects Tiffany. “When we first started seeing Ruben, just the individualized care, and the high quality of him taking the time to evaluate their gaits and develop something that worked for them—I can’t even tell you what a blessing it has been. I think it just goes back to giving the kids confidence and allowing them to be who they truly are!
“We feel very grateful that the kids have such a wonderful multidisciplinary team of medical professionals who care for them. They continue to see specialists at AdventHealth Orlando, Nemours, and their new neurologist at the Arnold Palmer Hospital for Children in Orlando–who is also awesome!”
So far, their journey has been filled with challenges and unknowns, and perhaps there will be more to come, Tiffany realizes. “But now that we are kind of settling in and they’re getting the care that they need, we’re able to say, ‘Okay. They’re in a safe place. They’re able to be themselves.’”