Why is there paternal, for fatherly, fraternal, for brotherly, but no similar word for sons?
If paternal is "relating to someone's parents", and fraternal "relating to someone's brothers", is there, or why isn't there, a word for "relating to someone's sons", i.e: sunternal Sentence example: "sunternal love"
Solution 1:
There is filial, from Latin filius "son" and filia "daughter". So filial love should work in most contexts.
Solution 2:
Perhaps "progenic" would also be a suitable candidate. Progenic is the adjective form of progeny - which means "child or offspring".