- a girl brought up with another child of different parents.
Origin of foster sister
Examples from the Web for foster sister
Historical Examples of foster sister
For the moment Dan forgot his complaint in the tender thought of his foster-sister.The Inn at the Red Oak
She drew her foster-sister away from Lennon with a grasp as resolute as it was gentle.
Yet she was no less mystified than Lennon by her foster-sister's manner.
Elsie struggled free from Lennon to fling her arms about her foster-sister.
Carmena checked her indignant protest and gazed down at her foster-sister.