So I had a family with a mom, dad, teenage son and child daughter. The dad cheated so the mom divorced him and he moved out and married his mistress. She then started dating a single dad who had a teenage daughter. She asked them to move in when they were still dating. The teenage daughter of the man and teenage son of the mom started interacting romantically. The girl got him to break up with his girlfriend and they were romantic interests. Then the dad proposed to the mom and they teenagers couldn’t interact romantically anymore even though they seemed to really love each other.