> I could easily tell why it was there: it was part of a partition for a closet.

> Except that over time it had become accidentally load bearing

> through other (ill conceived) changes to the structure this stud was now helping hold up the second floor of the house

Evidently, you couldn't easily tell why it was there. Moreover, I'm not persuaded that it accidentally became load bearing. It seems quite plausible that it deliberately became load bearing, for reasons which are ill conceived to you but not to the people who had them.