The thing is, Sirius would even agree with Remus. To a point, at least. Just because he didn't do it directly doesn't mean Sirius doesn't blame himself somewhat for what happened.

He nods, looking to her. "If you meet a man named Sirius Black...be careful. His magic has probably been restricted, just as mine has. But I don't know what he's been left with and...magic can do a lot. If you have the right belief and desires behind it, at least."