Kevin Costner has filed a response to his wife Christine Baumgartner’s divorce filing, expressing surprise at her decision to end their 18-year marriage. Costner, the star of the hit TV series “Yellowstone,” is requesting joint custody of the couple’s three children — Cayden, 15, Hayes, 14, and Grace, 12. His attorney, Laura Wasser, submitted the documents on Tuesday.

Baumgartner, a designer, cited “irreconcilable differences” as the reason for the split and filed for divorce on Monday.

She also requested joint custody of the children.

Following her filing, she was photographed without her wedding ring on Wednesday.

In a statement released on Tuesday, Costner’s representative said, “It is with great sadness that circumstances beyond his control have transpired which have resulted in Mr. Costner having to participate in a dissolution of marriage action.”

A source close to Costner revealed to Page Six that the 68-year-old actor was “very surprised” by Baumgartner’s actions.

The insider noted that Costner “obviously doesn’t want the divorce, and he would take her back.”

They added that the separation is “disappointing” for the “Bodyguard” star, as he still loves both his wife and their children.

In recent days, Costner has faced numerous cheating accusations.

However, the same source insisted that infidelity was not the cause of the divorce, stating, “There was no issue of cheating at all.”

Just one day before Baumgartner filed for divorce, Costner was photographed smiling and wearing his wedding ring.

The couple married in 2004. Before his relationship with Baumgartner, Costner was involved with Bridget Rooney, with whom he shares a son, Liam, 27.

Costner’s first marriage was to his college sweetheart, Cindy Silva.

They were married for 16 years before divorcing in 1994.

The former couple has three children together: Annie, 39, Lily, 36, and Joe, 35.

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