Rachel Weisz has a sense of humor about the upcoming addition to her family with husband Daniel Craig

Rachel Weisz has a sense of humor about the upcoming addition to her family with husband Daniel Craig.

The 48-year-old actress joked about her growing baby bump during her appearance on The Late Show with Stephen Colbert on Thursday. The host noted her new movie Disobedience, out now, but couldn’t help also asking about the actress’ next chapter with Craig, 50.

“The big news right now is you and your husband Daniel Craig have a big announcement,” said Colbert, alluding to Weisz’s pregnancy reveal on April 20. “Some people may not know. Would you like to tell them what it is?”

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“Um, I think it’s kind of visible, I guess, right?” said the Oscar winner, laughing. “I mean, I can say it.”

“For all I know, it’s a burrito,” cracked Colbert.

“Too much pizza!” said Weisz. “Yes, I’m pregnant.”

With both Weisz and Craig leading a quiet life in New York City, Colbert wanted to know if their new child will be “raised American or English.”

“Is it going to be an elevator? Is it going to be a lift? What’s the child going to grow up with?” said Colbert.

“I suppose it will have to be bilingual,” said the British actress, making the audience laugh. “So, there are other words that come to mind… Well, for a baby, we don’t say diaper, we say nappy.”

Night of Opportunity Gala, New York, USA - 09 Apr 2018
Credit: Erik Pendzich/Shutterstock

On Wednesday, Weisz shared an update on how her pregnancy is progressing.

“Doing pretty good now,” Weisz said on Good Morning America. “I was feeling very dodgy for about four months, but now the good bits kicked in.”

This won’t be Weisz and Craig’s first time navigating parenthood, though: Weisz shares a son Henry, 11, with director Darren Aronofsky, and Craig has daughter Ella, 25, with ex Fiona Loudon.

“It’s not surprising that they want a child together,” a film source recently told PEOPLE of the couple, who wed in 2011 after six months of dating. “They are both smart and secure and having a child is a natural next step even though both have children from other relationships.”

RELATED VIDEO: Rachel Weisz Reveals She’s Expecting First Child with Husband Daniel Craig

The source added: “They admire each other and want to keep their marriage alive and exciting. She is independent and their marriage is solid. Having a child is a natural desire. They have been married long enough to know each other, which is a mature step to be sure nothing goes wrong.”

Weisz first shared the pregnancy news in an interview with the New York Times, telling the publication, “Daniel and I are so happy.”

Continued Weisz: “We’re going to have a little human. We can’t wait to meet him or her. It’s all such a mystery.”