The straw hats are main characters that fight for themselves they have major fights with In the arc that there in. Yes they do fight underlines. That always stable series. Luffy fights major boss while his crew deals with The underlings. Why are you comparing spoiled baby bitch like momo Who has no particular fighting skills whatsoever? Your only response roger, whitebeard, and kaido had children on there crew. Look how they turn out. So what? He is not fight anyone through out entire series. So going relay others save him. Gtfo stay the hell home than. Your not character That crew needs. This kid doesn’t help luffy accomplish his goal surpass shanks one day. It goes against reflection during separation in the pretimeskip. In other words a motivational drive to help others and be better luffy future. This is brand new era. I didn’t see shanks asking child join him. Neither did ace. Blackbeard probably doesn’t have a child with him either . Luffy might give similar response that both shanks and ace did to children. We don’t see other supernova take children with them.