Amanda Seyfried Jokes About Future Plans: 'Definitely Third Mamma Mia! , Definitely No Third Child'

Amanda Seyfried is game for another round of Abba's greatest hits.

The Academy Award nominee, 35, spoke about motherhood and Mamma Mia! on Friday's episode of The Late Show with Stephen Colbert and joked about how she preferred doing another movie over having another child, telling host Stephen Colbert: "Definitely third Mamma Mia!, definitely no third child."

"If it was up to me, yes, of course, there would be eight Mamma Mia!s. Do you know how much fun that is?" she said, later dream casting the potential third installment with Colbert and her Les Misérables costar Hugh Jackman.

Mamma Mia! producer Judy Craymer teased a third film last summer, noting that the musical is "meant to be a trilogy." Seyfried has expressed interest in the past, but she's also admitted, "I don't think there are enough ABBA songs to make a third movie."

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RELATED: Amanda Seyfried's 7-Month-Old Son Makes Rare Appearance During Today Interview

Amanda Seyfried/instagram Amanda Seyfried and Thomas Sadoski

Seyfried welcomed a baby boy named Thomas Jr. in September with husband Thomas Sadoski, 44, with whom she also shares 4-year-old daughter Nina.

"No, I didn't read up on anything," she told Colbert of preparing for her second child. "I was like, 'It's gonna come to me. I got the instincts. I'm a mom now!' "

The Mank star added, "And it turns out, I could care less about the things I learned the first time. And I'm just going with the flow. In fact, I haven't slept for two months."

Seyfried later told Colbert that parenting two kids "is the hardest," also joking, "Remind me not to have another baby."

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Amanda Seyfried and son

Baby Thomas recently made a rare — but adorable — cameo in Seyfried's interview on Sunday TODAY with Willie Geist.

"There's some benefits and there's some serious drawbacks," Seyfried said of doing press from home, ahead of her first Academy Awards as a nominee. "They squeeze in so much more work. The benefits outweigh everything. I've got my kids in the house."