Sim suddenly has a relationship with another Sim

Problem

My Sim suddenly has a relationship with another Sim they don’t even know that well. This can be close relatives as well as children.

Before Photo Booth After Photo Booth
Family Tree after Photo Booth

Cause

This very bad bug is caused by the photo booth. Whenever you take a picture with another Sim (doesn’t matter which one) they are in a relationship afterwards, messing up family trees and relationships with other Sims.

Solution

Only use the photo booth with your real partner atm.  If  you had someone else as a partner, you can have them take a photo together and they should be back in the relationship but this does not correct messed-up family trees.

Mods that help with the issue

  • MasterController lets you correct the messed-up family trees.
  • Cleanup Genealogy on Overwatch corrects the issue