Luffys siblings

 Now, all you provided for doing is add every one of the additional 9–10 months, because that is how kong the excursion from East Blue through the Grandline has lasted, if not even the entire year, and that is their age. 

At Foosha Island: 

The preamble of the anime is when Luffy previously ate his demon foods grown from the ground saved by Shanks. At this young age, he was extremely intrigued by the force of the Pirates, motivating him to head out and discover the fortune, One Piece. Luffy meets Ace and Sabo, who become his siblings, in as old as. Luffy was fourteen when Ace began his excursion to the ocean. And if you really want to know how old is luffy  please visit theinfotrunk.