Yeah, Tracy being wild when she was younger was established so Sunny getting it from her wouldn't be that big a deal though still IMO it seems way too quick where Marcus didn't have to put any work in and it still would be nice if the other "love", I'm to the point of refusing to call it "alpha" because the MC seems to have less balls now than he did back when he still had the Adam Ruins Everything guy hair cut. I'm still not sure how much stats actually mean beyond whatever choice fork (and how much of the diplomat route is there really? Assumed that would involve the MC and Marcus watching each other and eventually double teaming girls, including Sunny and Tracy while in the Alpha route the MC would eventually make Marcus the "beta" including banging Marcus's mother with a story that hasn't progressed in what seems like two years or close to it. I still think this was originally more ambitious than how it's turned out which is understandable with how much more work is required with each route and there's already a lot of complaining about the other one being neglected.
From what I was told a while ago, before .3 or .4 the MC, Tracy and Sunny were blood related and not steps and I'm still not sure how old the MC and Sunny were when their parents got married and they all started living with each other. The intended blood relation was a better reason it'd be a more slow burn, even the step angle would be fine depending again on how long it's been since they all moved in together.
I just hope shit doesn't just end when the MC gets with Tracy and Sunny. That's been IMO one of the worst trends with some games, MC finally get the girls on the pedestal and after a vanilla sex scene or two it's the end.