Who is Sheila Rogers from Gone for Good and what is their importance?

Sheila Rogers was hired by Ken Klein to peddle drugs on a college campus. She quickly gets Julie Miller hooked on drugs, and soon after, she runs away to Stockholm where she meets Nora Spring. Nora and Sheila trade identities to keep those searching for them off the track. Sheila lives with Ken and pretends that Carley is her biological daughter. She later dies after being brutally tortured.