Sabo

If it weren't for the Sabo incident and a troublesome brother like you, I probably would not have wanted to live....

- Ace mentioning Sabo minutes before dying. Chapter 574, pg. 12

Sabo is a 10 year old boy who lives in Gray Terminal, and is a friend of Ace. He and Ace are secretly saving money to buy a pirate ship together. He is the same age as Ace.

Appearance
He has a chipped tooth. He wears a large top hat with a pair of goggles around it as well as a jacket and a scarf.

Personality
Not much is known about Sabo's personality at this time. He seems to be protective of his dreams and goals as he agreed with Ace that the two of them had to kill Luffy so that he couldn't tell anyone about their treasure.

Abilities and Powers
Like Ace, he carries a long staff around with him. He has sufficient physical strength as he and Ace were able to tie Luffy to a tree (a noteworthy feat since at that time, Luffy was already strong enough to survive a treacherous jungle), and then pin his head against the trunk when he tried to yell. He appears to have good thieving skills as well, since he was able to rob so many people to get their money and valuables.

Trivia

 * In Ace's dying words, he stated that Sabo was one of the reasons that made him want to live.