Eoleo

Eoleo (レオレオ Leoleo) is the son of Briggs and Chaucha from Champa. On several occasions he is seen using Psynergy which leads the player to believe he is an Adept. It is assumed that Eoleo used his Psynergy power to free Briggs from the Alhafra prison which allowed Briggs and his crew to escape to steal the ship.

It is revealed through Chaucha that Eoleo obtained his powers when he was struck by a falling Psynergy Stone stone, in much the same way as Feizhi.

Eoleo's Psynergy
There has been a lot of speculation about Eoleo's Psynergy. Since neither of his parents, as well as no one else in Champa (except perhaps his great grandmother), display any ability, so many theories have been forwarded. However, given that he showed his abilities after he was hit with a falling Psynergy Stone, and that his great grandmother is a descendant of the ancient Ankohl civilisation (according to a Mind-read Champan), the most logical conclusion would be that the falling stone unlocked his innate powers, as they had done with Tret and Feizhi in the previous game.

Element
Some people think that he is directly descended from the Ankohl who built the ruins to the north, unlike the rest of the Champans, who presumably have lost their ancestor's talents or have lost the purity of their blood. Considering the Ankohl's apparent ability to forge metal and the themes of the puzzles in the ruins, which heavily utilised the Sand Psynergy, this would make him an Venus Adept. This is the most accepted theory. With this theory in mind then, it would be hard to propose that the character with red hair in the promotional artwork for Golden Sun DS is Eoleo (although he may still make an appearance as a grown-up non-playable character).