Search on field = <empty>
I tried to look for orphans in a list, that means Mother = <empty>.I tried a few tricks like " " and space + tick (exact match) but it didn't work and even gave an error.
I saw another question for a possibilty to search for natural children (father = <empty>)
Technically, this should not be difficult to implement.
Either you could allow this on all fields (may be processing issues then), or just provide it for parents. It could be a code like "" or <> or a tick box on the fields that are deemed useful.
Thanks for looking into it.