In the latest chapter Kaido mentioned that he has a son.
What if we’ve seen him in two old chapters?
In chapter 675 page 12 there is a bald individual with horns similar to Kaido’s.
Then in chapter 692 we see this individual while he says “Tell Jack about this.”
What can we infer from this?
This person isn’t Kaido since Kaido is not bald.
This person is the one who sent Jack on the mission to retrieve Caesar.
More than likely this is Kaido’s son and as many fans speculated, he’s the “Ace” in he crew of the Beasts Pirates. The head in charge of the Calamities.