It is matter of time..luffy s grandpa... His father will eventually show their self... ╮( ̄▽ ̄)╭
but it will be to late for them to show and will just wait for luffy to defeat Mingo KYAAAAA~ cant wait sheshe XD it will be over soon :)
i think maybe law?
Certainly not Law. He has his own crew. I bet on Jinbei or Viola or Barto. lol Barto would be a good defense crew which they seem to lack.
Who dya think will join next who knowsヾ(☆▽☆)