See, I actually hate that the pregnancy was nothing more than a plot device. Someone discussed it well on Tumblr but I'll try to explain why here.

The 'baby' existed for exactly as long as the knowledge that Walter and Happy were married. We find out literally a minute ater Toby figures out it's Walter, and it ends moments after he gets his citizenship. Which means it served to completely erase any feelings or discussions that Quintis might have had in regards to this. Whie I've always been completely on Happy's side regarding this secret, it'd be unrealistic to believe they had no discussions about it but the writers completely are able to jump over any tension or conversations they might have had over it because it was distracted by the pregnancy, then as soon as the marriage is over, so is the pregnancy, so they don't have to commit the show to a baby, but they also got to avoid having Quintis deal with the marriage thing onscreen. So I feel like it was a lazy cop out.

I agree with not liking Paige bonding with Tim at the expense of her family, though. Sylvester dated, fell in love with, and married a normal without this schism between geniuses and normals being exacerbated, and while Paige and Tim are two normals, her characterization from the start has been someone who may be confused by them, but who wants to love and protect and teach them without being abrasive or condescending or dismissive, and since she's gotten with Tim, it feels different (Hard Knox is the biggest example but ever since that happened the littler things bother me too).