He’s said he wasn’t supposed to reveal the secret, but he did anyway!

Robert Downey Jr. told Jay Leno on The Tonight Show on Dec. 5 that he was “not permitted to discuss” the sex of the baby-to-be, but he blurted out the answer anyway: It’s a boy!

“S—, I did it,” he joked as he put his head in his hands. The 46-year-old is expecting his new son with wife Susan in late February, and he says he suspects he’ll be a very involved father.

“I think actually it’s been tougher on me,” the Iron Man actor joked about the pregnancy. “Just the hormones and the moods stuff and the nausea, and the whole thing.”

Jay even gave him a prosthetic breastfeeding device! “Who’s first?” he asked the audience as they cheered. “I need some practice!”

Congrats on the good news!

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