Kevin Costner’s wife Christine Baumgartner has filed for divorce from the “Yellowstone” star after 18 years of marriage and three children together.

The split is said to be due to ‘irreconcilable differences,’ with Baumgartner asking for joint custody of their kids.

Costner filed his response to the divorce on Tuesday, and he is also seeking joint custody of their children.

The 68-year-old actor and 49-year-old Baumgartner, a model and fashion designer, started dating in 2000 and tied the knot at Costner’s Aspen, Colorado ranch in 2004.

Baumgartner is not said to be filing for spousal support.

Costner’s attorney hinted there is a pre-nuptial agreement between Costner and Baumgartner.