"Lily isn't pregnant, because Harry's already been born from the point in time she's from," Sirius explained. That was all he was going to tell James there. The rest was up to Lily.
"And she wasn't pregnant when I ended up here so I don't remember any of it. But Remus is somewhere in his thirties so he'll remember it?"
He grinned, anticipating how James would react to that bit of news.