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

Isabella's story is about what life is like a foster sister.

From BBC

Alexa had learned to speak English, bonded with her foster sisters and captured their hearts.

From Washington Times

“I touched my old foster sister’s phone once. Big mistake.”

From Literature

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