"Bit human, isn't it?" Handy replies to Daine. "I mean, nothing wrong with human, of course, but. Well. It's not very me, is it?"

He pauses, giving the Doctor a funny look. "It wasn't Donna?" he asks, confused. He still assumes the Doctor already knows all about his origins from being there, so the only reason he'd be confused on that point would be if he had reason to suspect it had been someone else. He's honestly a little relieved by the idea, if perplexed -- if this Andrew came from some other human, he might be quite different from Handy after all.