Hashizou Katou

His real name is actually Hideki, but he was renamed "Hashizo" by his brother Go when he went to live with him after the death of his parents. Hashizo is actually Go's half-brother, being the son of Go's father and his mistress. After their death in car crash, Go decided to look after his baby brother although still very young himself, and they have been living together ever since. Hashizo is a very responsible little boy and, because of Go's career as a musician, he spends a lot of time alone with his best friend, the cat Juliano. When he meets Yakko, he will become very attached to her and the "Mambo" will become his second home. (Wikipedia)