The rot starts early because like a Patterson, April gets pissy when she doesn't get what she wants:
and because Mr B bonded with Becky too damned easily:
and because Becky had Liz and Candace's bad habit of trading on her looks:
and above all, she didn't want to humiliate herself to make a Patterson indulge in a power trip:
This last thing caused April to waste the rest of the strip being pointlessly angry at Becky because she refuses to admit to being filled with envy:
but instead blames natural feelings on the person who inspires them:
because the binary insanity that drives Lynn.
Also, one must remember that she's a Candace-like dumping ground for Lynn's free-floating hatred of the popular girls:
and lack of empathy towards children who don't do their job of being the goo that sticks man and wife together:
because it's a damned sight easier to make pious noise about family politics than it is to give a shit about someone who just bugs you.