When he heard the knock he immediately went to get it, pleased to find his mother. Plus he got to intercept her.
This was why keeping the whole 'we're about 800 years old, give or take' secret was a pain in his ass. He needed George to come tell Isabelle of the truth, so she would understand more.
Yet he smiled, "Mother," he gave in his native tongue, knowing Isabelle couldn't understand the dialect. "She doesn't know, by the way. And you don't look the correct age to have mothered me." He sighed, "But thank you for coming."