He married a descendant of Simon de Bouillon, chamberlain of Antioch, then a daughter of Constantine of Baberon, Lord of Barbaron and Partzapert.
[1] He was constable of Antioch when the city fortress was attacked and besieged by the Mamluks under Sultan Baibars on May 14, 1268 .
Since Prince Bohemond VI was in Tripoli, Simon commanded the defence.
From captivity he tried to negotiate a capitulation of the city, but the remaining defenders rejected this and offered the attackers fierce resistance despite their great numerical inferiority.
Finally, on May 18, the city was stormed and sacked by the Mamluks, and the remaining population was massacred or enslaved.