Locked Garden by Gloria Whelan

This story is set in the early 1900's. Two young sisters, Verna and Carlie, have recently lost their mother. Their father, a doctor, decides to take a new position as a doctor at an assylum! This doesn't seem to be a very pleasant environment for two young girls in which to grow up, but the girls learn to appreciate those who are different from themselves. In fact, one young patient, Eleanor, from the assylum comes to work in the doctor's home. The girl's very strict Aunt Maude becomes very jealous of the girls' affection toward Eleanor.

I loved this story!