"It's nothing really important. You mentioned dogs, I thought responsibilities, and then I thought about a discussion I had with Sirius about children and how he didn't want any and I do... not with him, but in general." He shook his head. "Really, it's not important."
He laughed. "Thanks for the offer, but it's not the house that's the problem. It's work, and all the extra work that I've been getting. It's nothing about the house or the people in it, but thank you for the offer."