Partnered Sims turn into siblings

Hi, I'm here on behalf of someone else, who had this bug identified through the PlumbBuddy app, which can scan save files for it and alert players when it happens. In their save, they have a couple (Advaith Acharya and Georgia Potter/Archarya) who were not related (Slot_00000005, named Harry and Hermione). He existed as a single parent with no other family. She existed with an extended family tree including siblings, parents, and grandparents.

Then the couple got married and she adopted his daughter, and suddenly he was her sibling while still having a romantic relationship (Slot_00000002, named Harry and Hermione 62).

Their household is called Potter, and they live in the residential rental unit 3 High Street in Nordhaven (left side, a multi unit lot called Godrick's Hollow). His name is Advaith Acharya and her name is Georgia Potter (in slot 5) or Georgia Archarya (in slot 2). His daughter, Samara, lives with them.

The person whose save it is isn't familiar with the forum and asked me to submit this for them. I'll submit the files according to the instructions for doing so, along with a text file copy of this comment.