When he grew to adulthood, he became, along with his brothers Roger, duke of Apulia, and Alfonso, prince of Capua, one of his father's chief men on the peninsula, while the king himself remained mostly in Sicily.
As he matured, he became, alongside his brothers Roger, duke of Apulia, and Alfonso, prince of Capua, one of his father's primary advisors on the peninsula, while the king himself mostly resided in Sicily.