There's a sudden surge of anger: real, passionate, burning anger at the idea that someone else has looked at Sophie in that way, because how dare they, and how dare they knock her up, and Peter is going to get--

Finally, the dots connect. Peter. Is married to. Sophie's sister. The anger is gone as quickly as it comes, and is replaced with complete relief. He can't help melodramatically falling to his knees, flopping his head into her lap with a laugh. "Sophie Berthier, love," he pleads, looking up at her adoringly, "you're a terrifying woman."