Lilly Stiernagle loves to do twirls. She can hit all five ballet positions. She skips, sashays and walks on her toes. And she’s exceptionally good at doing the splits.

But that’s where Lilly has an advantage over the other 5- and 6-year-olds in her dance class.

Lilly has no hip sockets. She has no femurs, no knees, no fibula. With only cartilage at the top of her tiny legs, Lilly has no trouble slipping down into the splits.

“She’s very flexible,” her mother, Jenny Stiernagle, says. “It doesn’t bother her at all.”

Lilly was born with an extremely rare condition known as Proximal Femoral Focal Deficiency, or PFFD. There are different degrees of the congenital anomaly, from short or undeveloped femurs to a lack of bones entirely; Lilly has the most severe form.

That doesn’t stop the 6-year-old Easton girl from dancing, though. It doesn’t stop her from doing anything, actually. Although she uses a wheelchair to navigate hallways and long distances, she can walk, climb and do basically everything on her own. So when she chose dance lessons over gymnastics last fall, her mom wasn’t at all worried about how she would fare.

“I figured it would be like anything else that she’s had to figure out,” Stiernagle says. “When she needed to get up to the sink, she just pulled out the drawers like steps and climbed up. So I knew she wouldn’t have issues with dance.”

Brittany Bisel, a partner in the Wells-based Spotlight Dance studio who has been Lilly’s teacher for the past year, wasn’t so sure. She was preparing to work with a child in a wheelchair when Lilly rolled into the gym.

“I was worried,” admits Bisel. “But then, on that first day of class, she just popped right out of her wheelchair and walked over. She works so hard and smiles through the entire class. She is just wonderful.”

In fact, Bisel hasn’t changed anything about the way she teaches to accommodate Lilly. The 12 kids in the class all do their foot exercises together. They all hop on one foot and walk on their toes. They all leap over their shoes.

If the leaping gets to be too much for Lilly (the exercise takes the children throughout the gym, and they often move quite quickly), she helps Bisel with the music instead.

Bisel has been dancing since she was 3 years old. She studied dance at Minnesota State University and at a studio in Minneapolis. She’s been teaching full time for the past four years and became a partner at Spotlight Dance two years ago. She’s never encountered a dancer like Lilly before. But she is impressed by Lilly’s eagerness to dance and her ability to keep up with the class — and the effect she has on the other children.

“Everyone wants to be next to Lilly,” she says. “They want to stand by Lilly, sit by Lilly, be partners with Lilly. Everyone loves Lilly.”

It’s easy to love Lilly, with her infectious smile and bright eyes. But sometimes the attention is overwhelming for her, and for her three younger siblings. The Stiernagles try to be open about their daughter’s condition and to downplay the glances she gets in public places.

“Our 4-year-old Lydia helps push Lilly in Target sometimes, and she notices people staring at her,” Stiernagle says. “I just tell her that people aren’t used to seeing kids in wheelchairs. And if we’re at a park or someplace with other kids, I’ll just explain it right away, so that there aren’t the stares and the whispers.