Rory Williams character study: I know
Now. Amy tells Rory she can’t have children- that’s the big awful secret that drove their relationship almost to breakdown- and he says he knows. He knew all along she couldn’t have children!? Wait, what?
So…I think Rory did know, he knew perfectly well she couldn’t have kids- but he thought she meant psychologically. After having one child under such terrible circumstances, and pretty much having to give it up, Rory would probably understand perfectly well that another kid wasn’t a good option for Amy. He knew, he’d accepted it a long time ago.
Watch his face in the last gif, when Amy starts talking about Demon’s Run. That’s a look of realisation and horror. He thought he knew what was going on- maybe that was even the reason for the earlier I love you more than you love me; a case of I tell you important things but you don’t extend me the same courtesy, I want to help you but I have to guess at your secrets!
But he was wrong.