Game Lags like crazy when not on pause

Playing the Sims 2 Legacy Collection

Everything was running smoothly for the past few days, played about 10 hours. Suddenly, my sims comes home with a coworker (happened a lot with no issue) and the child comes from school with a friend at the same time. Since the bus got loaded, the game is going at 1 frame per minute.

If I PAUSE the game time, everything runs perfectly smooth. It's only on play that everything goes crazy. I don't know if it's one of the 2 sims that came in that is causing the issue. I tried going back to the neigbourhood, restarting the game and restarting my computer, nothing worked.

I tried using the "Repair" fonction of the launcher as well, nothing changes anything. My last hope is to ask the sims to leave and wait an hour until the sims manage to leave =__=

Anybody has a fix for that?