Only groups that will happen are those that make sense.
Jenna has nothing to do with Lily or Deb so that grouping makes no sense at all. Likewise Monica won't touch any of her kids (and the lack of incest in game) so having the family trio most likely won't be a thing.
Why? Why would you crush my hopes and dreams like that?
Also Jenna likes to watch, she's a voyeur. Deb likes to watch Lily and Lily likes to be watched ergo makes perfect sense.
Also Monica wants her daughters to be happy and if they are happy living with the MC at the beach house then she, as a good mother, wouldn't want to ruin that. Monica doesn't need to know the particulars of what goes on in the beach house
Also if the MC wants to come over to Monica's house from time to time with a bottle of wine to make some more photo shoots with Monica and Zarah and one thing led to another..well.. that is just human nature.
Also Katie and Jenna in the same bed would not be incest because there would be an MC, Lily, Debbie or even a Jolina, Angel, Wanda, Elaine, Bella or a Zarah-sized separation in between them, at all times, see...no incest