Kozuki Momonosuke

Momonosuke (モモの助) is the son of samurai-head that Sanji and rest of kidnapped Straw Hats found.

History
He was first mentioned in chapter 657 when the samurai told Sanji that he came to Punk Hazard to save his son. His name was revealed when the samurai was asking if the giant children in Biscuit Room had seen him.