Is there a smart way to locate a sim's gravestone?

I couldn't find the gravestone of one Sim, but I did notice that gravestones can't be destroyed if the ghost is a playable member of the household. So to recover the missing urn, I invited the ghost into the household then bulldozed the lot. The urn appeared in the family inventory. Released the ghost later.

Probably an extreme method, but it got the job done.