They REALLY need to add a step-parent relationship...

I really don't understand why this isn't already a thing. They need to look at what they did with 3 and repeat it here, all relationships seemed accounted for and we had more relationship options in CAS. Not all family members seem to show up on a sims family tree as well, I can't see a sims in laws unless I click over to the sim that connects them. When your son gets married and has kids, his wife is part of your family, no idea why the game acts like they're not connected.