She knew now, she thought, what nuns who were bricked up alive in convent walls felt like.

Suddenly she gave herself a little shake.
"Don't be a silly little girl," she said.

She was always very angry when anyone else called her a little girl, even if the adjective that went first was not "silly" but "nice" or "good" or "clever." And it was only when she was very angry with herself that she allowed Roberta to use that expression to Bobbie.
She fixed the little candle end on a broken brick near the red-jerseyed boy's feet.

Then she opened Peter's knife.

It was always hard to manage--a halfpenny was generally needed to get it open at all.