Kieran Culkin is set to become a father for the third time

In pictures from the red carpet, the 42-year-old actor can be seen with his hand placed across his 37-year-old wife's bump.

The pregnancy comes after Kieran implored his other half to "get cracking" on having more children as he picked up the Academy Award for Best Actor in a Supporting Role in March.

The star - who took the prize for his work on A Real Pain - recalled how he had told spouse Jazz he wanted a third child while accepting his award at the Emmys last year and admitted they made a bet afterwards in which she said she'd complete their family with two more kids if he ever won an Oscar.

Speaking on stage at Los Angeles' Dolby Theatre, he said towards the end of his speech: "I should thank my mom and Steve for trying to raise me, you're really good people and gave it your best shot. I love you mom.

"I love you Jazz. I have to thank my wife Jazz for absolutely everything, for giving me my favourite people in the world...Please don't play the music because I want to tell a quick story about Jazz.

"About a year ago I was on a stage like this and I very stupidly, publicly said that I wanted a third kid from her because she said if I won the award she would give me the kid. It turns out she said that because she didn't think I was going to win but people came up to her and were really annoying her, I think it got to her.

"Anyway, after the show we were walking to the parking lot and she goes, 'Oh God, I did say that. I guess I owe you a third kid' And I turned to her and said, 'I want four'. She turned to me and I swear to God she said to me, 'I will give you four when you win an Oscar.' I held my hand out and she shook it and I have not brought it up once until now.

"Remember that honey? You do. Well, 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?"