"I know where the washroom is." She polished off her sandwich in a few massive bites. She had been pretty hungry, after all. "I did help you move in, remember?"
She was certain he did. He tended to have a long memory, and anyway, he probably made lists about such things just in case.
Either way, she really could stand to clean herself up and try to appear and least somewhat presentable. As for mum's state once she got home... well...