As the youngest of four kids in this close-knit Hinsdale family, 16-year-old Joanna Lagedrost knew her sister, Sarah, coveted a prestigious clinical research gig in Philadelphia for a year before starting medical school.

"I got her the job," Joanna says matter-of-factly, a slight smile accompanying her dry wit. "I asked her to pay me the small sum of $50 and she still hasn't ponied up the cash."

Enrolled in the University of Michigan Medical School next year, Sarah says she'd rather repay her debt to her little sister by helping find a cure for Friedreich's ataxia, the devastating, progressive disease that threatens Joanna's life and has no cure or reliably effective treatment.

"I'm obviously very motivated because of my sister," says Sarah, 22, a study coordinator for Dr. David Lynch's Friedrich's ataxia research at the Children's Hospital of Philadelphia. "I tell her I'll help her eventually."

Friedrich's ataxia is an inherited disease that attacks the nervous system and weakens muscles. Symptoms usually appear during childhood and grow worse, often landing teenagers in wheelchairs. It can damage the heart and sometimes kill patients in early adulthood.

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