No love here for April or Butch, when they were using and tormenting Catelynn about the adoption for sport. Those years were hard even to watch -- can't imagine living them, and unsurprised that Catelynn has continuing issues. But regarding the fight that led to Butch's imprisonment, I watched that episode recently, and April says that a neighbor called the police. April also showed Catelynn and Tyler a dent in the bathroom wall where Butch slammed her head (...) and marks on her neck from his choking her with a towel. April said that Butch was clearly on something and not himself, and that he had never attacked her before (and then the camera cut, interestingly, to Kim's very expressionless face). While I don't doubt that April and Butch have gotten into it more mutually (and less destructively) in the past, the incident that sent him to prison was apparently violent enough to surprise the whole family.
That said, April's insistence that Butch wasn't himself seems to be how she herself feels about -- she hasn't acted like she's afraid of him, and certainly she seems to have encouraged, and is continuing to encourage, Butch's non-legal relationship with Nick.
I'm of two minds about Butch's reaction to the parties. Part of me thinks he was trying to take responsibility for the fact that he'd gone to prison and it was his fault; part of me thinks he was deflecting blame and was frustrating he couldn't take part from the start. But it wouldn't be the extended Lowell-Baltierra-[April's maiden name] clan if there weren't some mumbled, unclear sentiments about past or previous drama, so there's that.
Nova didn't look too happy with the cake. In general, she looks much more like Catelynn to me, while Carly at that age favored Tyler. A not-very-nice part of me wonders if that has in an unconscious way affected the way her parents feel about her.