I am also having this issue! I have tried canceling on the calendar and It just won't go away. My sims relatives literally brought all their dogs and it's so crowded in her apartment! Please let me know if you get a response from EA ☹️
So if you’re looking to solve this I accidentally found a way… long winded but isn’t everything in the sims?
So I moved a sim (could be a random one I assume) into the household and as I did this a pop up said it would cancel the current stay over - I was glad as the parents had been there for a week in the 1 bed eco house I was living off the land in… anyway… it solved it. The parents were gone when the new sim arrived in the household and then I just moved that sim out again.
