Chris Pizzello / Invision/AP 1 / 13
Chris Pizzello / Invision/AP 1 / 13

Reported by UsWeekly

Robert Downey Jr. and his wife, Susan Levin, are expecting a boy!

The 46-year-old actor spilled the beans Monday night on the "Tonight Show" with Jay Leno. "I am not permitted to discuss it," he quipped. "I can't say a word ... We're having a boy!"

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The "Iron Man" star, who told Leno his baby-to-be is due in "late February," is also dad to an 18-year-old son named Indio with his first wife, Deborah Falconer.

"I don't wanna be presumptuous," he joked. "But I think actually [the pregnancy] has been tougher on me [than Susan!] ... Just the hormones on and the mood stuff and the nausea and the whole thing."

"I gotta be careful," he added playfully. "I am gonna have to see my wife sometime after doing this segment with you, and I think I'm already in trouble."

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The actor, who kicked his drug and alcohol addiction over six years ago, told Leno he plans to be a very involved dad.

He also appears to be a pretty good husband. Last month, the "Sherlock Holmes: A Game of Shadows" star took his pregnant wife on a romantic Hawaiian getaway.

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So will he continue help his wife when the baby's born, even when it comes to changing dirty diapers? "That's just poop," he told E! News in October. "That's no big deal."