A trans parent would likely still want to be called “Mom” or “Dad”, I assume. At least that’s the case with the few trans parents I know.
Parents don’t usually use “daughter” or “son” as pronouns, so I don’t think it would come up with non-binary children.
Do children of non-binary parents call their parents by their first name? It seems unlikely that they say “Parent, may I please have more screen time?”.
“Honored Ancestor” and “Blessed Forebear” are always appropriate.
Much respectful. So parent.
Nonbinary household with conservative upbringing. That would certainly blow the mind of certain people.
“Excuse me, honored ancestor, I need to defecate” - Timmy, 5 years old