She hadn't really upset him. Not really. It was just a tender spot because everyone else didn't seem to think that Peter was a mistake he gladly would have made himself, had it truly been his choice to make. "He is a brilliant mistake," Theo said, smiling at her genuinely.
He likewise clasps his arms around her waist, pulling her a little closer. "Shan't, hm?" he said, letting his mouth hover just above hers, lips almost brushing hers as he spoke. "Are you absolutely sure about that, luv?"
It was an endearment that he'd started using that first time she'd stayed over and had crept into his vocabulary with her progressively more, though he hadn't completely realized it.