Prince (Shahzada) Mustafa-Tommaso Sayd was the youngest son of Prince (Shahzada) Pierre-Muhammad Sayd and The Noble Maria-Concetta Doria, daughter of the Consul of Genoa. He was executed with his father. He was the brother of Prince (Shahzada) Oshin-Pierre Sayd, Princess (Shahzadi) Helena Sayd, Princess (Shahzadi) Concetta Sayd, Prince (Shahzada) Nicola Sayd and Prince (Shahzada) Ambrosio-Paolo Sayd. Prince (Shahzada) Mustafa-Tommaso Sayd was a grandson of Cem Sultan.