Toddler sim replaced with random sim

I played the new re release for several hours today, in Pleasantview with the Broke family. The mother Brandi miraculously was pregnant soon into the game even though she has no husband or romance with anyone. That’s fine, idc, I welcomed the baby. The baby became a toddler, his name is Tucker. Just before Brandi took her second son Beau shopping at a downtown lot a random sim (Oliver ) showed up to visit I guess. The first son, Dustin was at work, the nanny was hired for the toddler Tucker. I saved before calling the taxi, Brandi and Beau left for shopping. Upon their arrival back home the random sim Oliver that had been visiting was now a family member taking the place of Tucker. When I went into each sims memories the new baby or new family member name was replaced with Oliver, except Oliver is not my toddler, he’s some random teen. And he has no memories at all. So to say I’m pissed is an understatement. I tried closing out the game without saving but ofc the game auto saved upon their arrival home. Soooo that’s one way to break the game and make me not want to play any more. Any help is much appreciated, thanks for reading.