Adding to this!
I have a Sim who was going to marry and move into his wife's household, and I wanted him to have a particular painting made by his (still-living) Dad. So, before splitting the household, I had Dad make the painting into an Heirloom and then put it in Son's inventory.
I start playing Son's new household and put up the painting... and suddenly all Son's inlaws-to-be are getting "Better Off Dead" moodlets! I noticed that none of them KNEW the Dad who'd made the heirloom.
So, during the wedding, I made sure all the inlaws talked to the Dad. The next day, I had them look at the painting to "Remember Original Owner"... and got the Fond Thoughts moodlet instead.
Keep in mind, THE ORIGINAL OWNER HAS BEEN ALIVE THIS ENTIRE TIME. The only difference was whether the Sims had him on their Relationship panel.