Claudia Marcella
Following the civil wars, Iullus was granted high favours from Augustus, through Octavia's influence. In 21 BC Augustus wanted his daughter Julia the Elder to marry Agrippa, who at the time was married to Iullus' stepsister Claudia Marcella Major. Agrippa agreed to the marriage and so divorced Marcella. Marcella consequently obliged Iullus to marry her. Iullus and Marcella's sons were Lucius Antonius, Gaius Antonius and a daughter Iulla Antonia.