The marriage served to strengthen the position of Antipater among Herod's many sons as future King of the Jews. Antipater was killed by his father five days before Herod's own death according to Josephus. (Some records indicate a period of two years between Antipater's death and Herod the Great's death).
The union elevated Antipater's standing among Herod's sons, who would one day inherit the throne of Judea. Antipater was killed by his father five days before Herod's death, as per Josephus. Some records suggest a two-year gap between Antipater's death and Herod's passing.