Kieran Culkin has won the Academy Award for best supporting actor for his performance in “A Real Pain.”

In his speech, he brought up the infamous moment when, after winning Emmy Award for best actor for HBO’s “Succession,” he asked his wife, Jazz Charton, to have a third child — which he did only because she’d promised to have another kid if he won the Emmy, not thinking he would.

“After the show, we’re walking through a parking lot … and she goes, ‘Oh, God, I did say that!’” Culkin said. “‘I guess I owe you a third kid.’ And I turned to her, and I said, ‘Really, I want four.’ And she turned to me — I swear to God, this happened there’s just over a year ago — she said, ‘I will give you four when you win an Oscar.’”

In the audience, Charton acknowledged that she had, indeed, made that promise. “And I have not brought it up once until just now,” Culkin continued. “I just have this to say to you, Jazz — love of my life, ye of little faith — no pressure. I love you. I’m really sorry I did this again, and let’s get cracking on those kids. What do you say?” Charton, while laughing, mouthed an emphatic “No!”

In “A Real Pain,” Culkin plays an alternately charming and exasperating Jewish man touring Holocaust sites with his uptight cousin, played by the film’s writer-director, Jesse Eisenberg. With his first Oscar nomination and win, Culkin concludes his sweep of the category this awards season; he also won at the SAG Awards, Independent Spirt Awards, BAFTA Film Awards, Critics Choice Awards, the National Board of Review and the Golden Globes, among several others.

Much like this awards run of the previous supporting acting winner, Robert Downey Jr. — who also presented the award — Culkin’s free-associative acceptance speeches have been a highlight of the season. (Downey even referenced this while presenting, saying to Culkin, “If you’d simply cease trying to be as witty as me when on an award season roll, you’d be perfect.”) At the SAG Awards, he thanked the guild for “this incredibly heavy award,” noting that “I don’t think there’s any way anyone can hold this for 45 seconds — which is the allotted time, Adrien Brody!” Culkin then promptly apologized to the star of “The Brutalist”: “There was no reason to take that shot. I love you. Take your time.”At the Globes, meanwhile, Culkin opened his speech by noting that he and his wife “did a shot of tequila with Mario Lopez,” which had left him a bit woozy. “Definitely feeling that! Whole speech is gone!”

In his Oscars speech, Culkin thanked Eisenberg for making the film: “You’re a genius. I would never say that to your face. I’m never saying it again. So soak it up.”

Winning the Oscar caps off an auspicious few years for Culkin, who also won multiple leading actor awards, including the aforementioned Emmy, for his performance as Roman Roy in the final season of “Succession.” He began his acting career as a small child, making his feature film debut alongside his older brother Macaulay Culkin in the 1990 comedy “Home Alone.” He played Steve Martin and Diane Keaton’s young son in 1991’s “Father of the Bride” and its 1995 sequel, and he played Meryl Streep’s youngest son in 1999’s “Music of the Heart.” But it wasn’t until his first leading performance, in 2002’s coming-of-age dramedy “Igby Goes Down,” that Culkin was able to showcase his ability to mix deft comic timing with a wounded melancholy — which he deployed to devastating effect in “A Real Pain.”

Famously, Culkin nearly dropped out of making “A Real Pain” just weeks before he was due to start shooting because he couldn’t bear to be away from his wife and two kids for a month while on location in Europe. Emma Stone, one of the film’s producers, talked him out of it with some savvy emotional blackmail. As Culkin explained in an interview in Vogue, “She goes, ‘If you don’t do it, the entire movie falls apart. But that’s not your responsibility. You shouldn’t feel that burden at all.’”

The other supporting actor nominees were Yura Borisov (“Anora”), Edward Norton (“A Complete Unknown”), Guy Pearce (“The Brutalist”) and Culkin’s “Succession” co-star, Jeremy Strong (“The Apprentice”).