Kevin Costner shares that two of his children have appeared in 'Horizon' films: "I simply attempt to capture them."

Family comes first for Kevin Costner.

"Horizon: An American Saga" features not only the 15-year-old son of an Oscar-winning actor but also other members of the Costner family showcasing their acting skills.

"Costner revealed that his seven children are all supportive of each other. In chapter two, his oldest son had a scene, and he played a small part again."

He quipped, "I simply aim to ensnare them."

Costner's ex-wife Christine Baumgartner is the mother of their children Hayes, 15, Cayden, 17, and Grace, 14. The couple divorced in February after 18 years of marriage.

He has three adult children - Annie, Lily, and Joe - with ex-wife Cindy Silva, and a 26-year-old son, Liam, with former partner Bridget Rooney.

Hayes, Costner's younger son, made his debut in the first film of the post-Civil War drama at the age of 13, while his older son appeared in the second part of "Horizon."

"They're all supportive of each other. My oldest son was in a scene in chapter two, and, a small part again. I just try to find ways to trap them." — Kevin Costner

Hayes' casting as Nathaniel Kittredge on set with Costner was unique in many ways.

"I'm so happy that he has that now for the rest of his life," Costner said. "I haven't pushed my children into this, and this might be his only dabble in it, but he's memorable. And for me to have him, I'll never forget it."

WATCH: KEVIN COSTNER TALKS ABOUT WORKING WITH HIS SON ON ‘HORIZON’

Filming for Hayes' role took two weeks, allowing Costner to bond with his son during that time.

Today," Costner stated that his son's role in the movie was a smaller part. He explained, "I wanted him with me for the week, two weeks, and we would drive to the set every day. He didn't have much experience, but he was beautiful in the movie. The scene was complicated.

In February, Costner unveiled the first trailer for his four-part post-Civil War drama, highlighting the Wild West landscape he has long been associated with, stemming from his early directorial work on "Dances with Wolves."

Besides starring in the movie, Costner also directed "Horizon," which he co-wrote with John Baird. The cast includes Sienna Miller, Sam Worthington, Luke Wilson, Abbey Lee, Jena Malone, and Giovanni Ribisi.

"I haven't pushed my children into this, and this might be his only dabble in it, but he's memorable. And for me to have him, I'll never forget it." — Kevin Costner

Despite the high cost of the film, which exceeded millions of dollars, Costner had to bear the brunt of the expenses out of his own pocket, which were later revealed during his divorce proceedings.

Costner later clarified the massive sum. He told GQ magazine that he has $38 million in the film, not $20 million as previously stated.

With "Yellowstone" officially ending, Costner can now concentrate solely on the future of "Horizon." Last week, he confirmed on social media that he would not be returning for season five, part B of the Taylor Sheridan show.

Costner explained his decision to leave the popular series by stating, "There are too many unanswered questions, so it's time to step away," in an interview with Planet Chronicle Digital.

Last week on Instagram, Costner announced that he would not be able to continue with Season 5 of "Yellowstone" after working on "Horizon" for over a year and a half.

WATCH: KEVIN COSTNER REVEALS HIS OLDEST SON IS IN ‘HORIZON’ 2

"The experience that transformed me was something I loved and I know you loved it too. I wanted to inform you that I won't be coming back. Despite the wonderful relationship we've built, I'll catch up with you at the cinema."

In the courtroom, Costner discussed the potential legal battle over the money he is owed from his role on "Yellowstone" while also fighting for child support payments with his ex-wife Christine Baumgartner. Prior to the judge's decision in September regarding monthly child custody payments, Costner provided a detailed account of the drama surrounding "Yellowstone" season 5.

"In the courtroom, he stated that they had negotiated, but there were disputes regarding creativity. He attempted to resolve the impasse, but they departed."

At the time of filming "Yellowstone," Costner was in post-production for the first movie in the four-part saga, which was a "critical" time for putting things together.

"During the filming process of 'Yellowstone,' they decided to make changes, which affected 'Horizon.' I had planned to do my movie 'Horizon' and leave the show, then do B. However, I was only working on a show once a year, but now it was being done twice."

Before the show's cancellation, Costner revealed that he had been offered $24 million for seasons five, six, and seven of "Yellowstone," but scheduling issues caused the breakdown.

"When asked by his ex-wife's lawyer if he had received a payout from the latest seasons of "Yellowstone," Costner replied, "I'm likely to end up in court because of it.""

The western saga starring Costner premieres in theaters on June 28, with the second part following on August 16. Tickets are currently available for purchase.