Sithil-Horak was the daughter of unknown parents. The date and place of her birth have not been found.
Her husband was Shapur II of Persia. They were married, but the date and place have not been found. Their five known children were Shapur III (?-0388), Ormizduxt (c0325-?), Vahram IV (?-?), Yezdigurd I (?-0421) and NN (?-?).