foster sister

American  

noun

1. a girl brought up with another child of different parents.

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Etymology

Origin of foster sister

First recorded in 1640–50

Example Sentences

When footage of Nazi soldiers appeared on television, Mr. Kertzer and his older sister, Ruth, would leap to switch the set off to protect their foster sister, Eva.

From New York Times • May 27, 2022

Their daughter, Dorothy, choosing from among photographs of six possibilities for a younger foster sister, chose Vera — for her smile.

From New York Times • Mar. 25, 2022

McLaughlin, who works at a therapeutic foster center, describes her 3-year-old grandson — who likes morning snuggle sessions and giggles with delight when his foster sister wakes from naps — as an “adrenaline junkie.”

From Washington Post • Jun. 30, 2017

There will even be a few numbers in the original three-part harmony: Maxene and Patty will be joined by a newcomer, Jane Sell, 32, who for the show's duration will be an Andrews foster sister.

From Time Magazine Archive

He thought of his foster sister Eva’s words.

From "Far from the Tree" by Robin Benway