the dad had custody of him so naturally if the dad passed, the mom would take him instead. as for the break up, Lee won wanted han gun to wait until they were in college to date again but since the dad passed and it traumatized/hospitalized Lee won, I'm assuming they lost contact or lee won just gave up the idea of dating han gun altogether since he moved away from seoul to live with his mom

If the dad died why Lee Won has to move? He's the only reason of Lee Won's angst... So why did they even break up? These 2 chapters are rushed ! Am I only not understanding it?