Adam Levine and Behati Prinsloo are at it again ... They're expecting another baby.

The model announced the news on Instagram on Sept. 13, posting a mirror selfie that clearly showed a baby bump.

"ROUND 2.....," she captioned the image of her in a two-piece.

The couple welcomed daughter Dusty Rose Levine in September 2016.

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"It's so fun. I do new stuff all the time, constantly entertaining," he told Jimmy Fallon about fatherhood in March. "It's the greatest thing in the world."

The Maroon 5 rocker and his model wife have long been open about their plans to have more children.

Only a month after the couple married in a beautiful ceremony in Cabo San Lucas in 2014, Adam said he was ready to jump start that baby making process.

"We're definitely going to do it," the "Voice" coach told Ryan Seacrest during a radio interview. He then joked, "I want to have 100 kids. I want to have more kids than would be socially responsible."

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Behati, too, has expressed a desire to make beautiful children with her rocker hubby.

While they were engaged, she told The Edit that there were "definite" plans in place in place to have children with Adam.

"I have no expectations. Not in a bad way, but I've learned that you can't plan ahead. I live day by day and see what happens," she said of the couple's future. "It's vague, but I like it that way."