Solved
Adult sims age up and then die
I age up my adults sims and then switch households and then the elders sims pass away the same day. All four of my elder sims passed away at the same time. I play on ps4! No mods or cc!
When you age up a sim in cas, they have the same amount of lived days as they did before you aged them up. If the days lived as an adult is longer than the elder lifespan that you play in the game then they will die straightaway.
