Katelyn and Karly Morris put aside the bicycle and hula hoops to campaign for psoriasis research.
Psoriasis is an auto-immune disease that can create painful and unsightly lesions on the skin.
In recent years, studies at the University of Pennsylvania School of Medicine have also tied psoriasis to serious problems later in life, including heart disease, diabetes, Crohn's Disease, and other ailments.
For the Morris Sisters, it's taken a physical and emotional toll.
Katelyn says. "During dance and stuff, you just kind of wear a leotard, and you don't really have anything to cover it. So like, it feels a little awkward cause everyone's staring at you and stuff, and they're afraid to talk to you."
Their mother, Christine, adds, "She was able to hide it pretty well for a kid. Unfortunately, it would be really hot outside and she'd be wearing sweatpants and sweatshirts."
"Karly had it primarily in her scalp, and she actually lost a lot of hair during that time, and eventually had a wig," says Christine.
Christine Morris says she really saw the self-esteem of her then-4-year-old daughter drop during her struggles with psorasis.
She says they had a hard time finding the right doctor, that they went from dermatologist to dermatologist before finding the person they felt comfortable with and who understood what the family was going through.
Topical and light treatments didn't work. Injections of methotrexate did put the psoriasis into remossion for a year. Christine says they occasionally have flares if they are getting sick. Their initial outbreaks came on the heels of an infection.
"The girls actually had a strep infection that they were passing back and forth," notes Christine. "They didn't show any symptoms, as many children do, but they were passing it back and forth."
The sisters are now activists for Psoriasis research, going to Washington to lobby Congress for more funding and awareness.
And on Saturday morning, they helped lead the Walk To Cure Psoriasis at the Philadelphia Zoo.
Getting involved was a big boost to the girls' emotional health. They made friends with other kids with psoriasis.
The Morris family say a cure is a must because of the recent discoveries of the long-term impact of psoriasis.
And the ongoing progress shouldn't be slowed.
"There are so many new drugs in the pipeline, and other avenues of treatment," says Christine.