Quote Originally Posted by Swordmaster View Post
Antiochos II married Ptolemaios' daughter Berenike.
His first wife was Laodike, the daughter of Achaios, his uncle. He later left Laodike to marry Berenike in order to seal peace with Ptolemaios II.

Btw., Antiochos, Berenike and their son were murdered by order of Laodike, so you can see where political marriages can lead to