Character from The Silver Sword by Ian Serraillier!

It was late at night, when the bombs dropped on Warsaw. The three Balicki children, Edek the middle boy, Bronia, the youngest girl, and Ruth, the oldest, had woken up from the loud sounds of screaming and bombs and bullets.

Ruth immediately hoisted Bronia onto her back, carrying the little one while Edek and her escaped through the window and running across the rooftops. While running, the three children noticed another girl, roughly around Ruth's age, positing herself up and running as well..

It was raining hard, so the children could only worry about themselves right now, but it was still hard to leave the girl behind..