It meant a lot to Emma that Ava and Nicholas had met their father and that he'd decided to keep them instead of allowing them to be sent away to Boston. Emma was generally a very closed-off woman, but it was pretty obvious to Mary Margaret that she didn't even care to try and keep her happiness under wraps tonight. It was nice to see that quietly giddy side of her, to have her open up to Mary Margaret a little, and even to just have a silly conversation… about Henry's idea of her being Emma's mother of all things!