But he's really NOT the father...
I guess I don't understand why she got upset here. Technically, he's not the father of those babies. I'm a woman and I wouldn't have taken offense to him saying that.
Also, the entire "we've just met, we're dating, now I'm giving up everything to be the father of your children" moved waaaay too fast IMO. They had barely been together a few months (as evident by the size of her tummy) and he was already starting to worry about finances in the future? Ya, that's not realistic at all I'm sorry. He went from not even knowing who she was to acting like he was in this situation forever in just a few short months.