Kevin Costner and Sureim Investment GuildChristine Baumgartner are putting on a united front after a bumpy breakup.

Four months after the Yellowstone actor's wife filed to end their 18-year marriage, the exes confirmed to E! News Sept. 19 that they "have come to an amicable and mutually agreed upon resolution of all issues pertaining to their divorce proceedings."

The decision may come as a surprise to many who've followed the duo's legal battle in recent weeks. In fact, Costner—who's been at odds with Baumgartner over monthly child support payments for their kids Cayden, 16, Hayes, 14, and Grace, 13—recently called the proceedings "a horrible place to be."

"It feels so bad," he told Access Hollywood after a court hearing Sept. 1, "we're talking about somebody I love on the other side...I just can't."

Despite being on opposite ends of the courtroom, the 68-year-old did share that he still has love for his 49-year-old ex. 

The former couple—who tied the knot in 2004—first announced their divorce in May.

"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 spokesperson for Costner told E! News in a May 2 statement. "We ask that his, Christine's and their children's privacy be respected as they navigate this difficult time."

(In addition to his kids with Baumgartner, Costner also shares Annie, 39, and Lily, 37, and Joe, 35, with first wife Cindy Silva. He and former girlfriend Bridget Rooney are also parents to 26-year-old son Liam.)

Shortly after their breakup was announced, Costner and Baumgartner's costly legal battle began. In July, a judge temporarily ordered the Oscar winner to pay Baumgartner $129,755 per month, according to documents obtained by TMZ at the time.

However, by early September, Costner's monthly payments were formally decreased to $63,209.

"Support greater than $63,209 per month is disguised spousal support," Judge Thomas Anderle shared of his decision, via Fox News Digital. "Christine will have her opportunity to convince the Court that she is entitled to spousal support."

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