"The characters you all want to play are not too closely related (in terms of potential/canonical reasons for interaction)" -- does my playing Zuko affect my chances of applying/playing Meelo?

I mean since Meelo is Tenzin's son and he's the grandson to Aang and Katara... A part of me feels like it wouldn't be allowed, but I just wanted to double check with you lovely people and get your input. c: