I think that often makes good sense! I mean, I imagine if trolls did have family members & understand the idea of "family" the way humans do, then probably family members would wind up filling some of the emotional needs that the pale and ashen quadrants do.

(I sort of love toying with how moirallegiance works with sexual relationships -- I have seen it done in fic both where being "moirails with benefits" is fine and where there *is* something paralleling an incest taboo against moirails being physically involved.)