Cathy is Tommy Sullivan's little sister. She's a couple years younger than him but older than the rest of the kids.

Cathy has gone from a quiet, somewhat reserved girl to an absolute star.

She's tiny, impossibly sweet and cute, and bubbling with positive emotions. It is impossible to dislike Catherine. People have tried and failed. Miserably.

Standing at about five foot tall, with golden curls and bright blue eyes, she seems even younger than her sixteen years. Make no mistake though, under those curls is a sharp, inquisitive mind that misses very little.

Her greatest weakness is also her greatest asset. She is unfailingly positive and believes the best of everyone. Fortunately it's almost never a problem for her.