Mystery Solved! Ryan Reynolds Reveals His Daughter James' Birthday for the First Time

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Happy birthday, little James!

A year after she was born, Ryan Reynolds finally revealed his daughter’s birthday: Dec. 16!

On Wednesday, the Deadpool actor tweeted, "Happy birthday to my baby girl! Sad I lost my virginity. But thankful I have a daughter."

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Blake and Ryan, who married in 2012, have been relatively private about their daughter, not revealing her name until March and sharing the first pic a few months later.

Ryan has fully embraced his new "dad role," joking with Jimmy Fallon in September that "I’ve definitely lost all cool," before the 38-year-old added, "I’m the dad guy now."

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"About a month ago, I was sitting in traffic and I was just jamming to 'These Dreams' by Heart," he recalled. "I was killin' it in the car and there was this busload of high school kids that were parked right beside me. I didn't even realize it. I looked over and every one of their jaws were just on the ground laughing their guts out at me."

Aww, Ryan! Although the actor may have lost some cool points, he opened up in July about how fatherhood has changed his perspective.

PHOTO: The First Pic of Ryan Reynolds' Daughter

"I suddenly feel an incredible sense of mortality like a lot of other fathers do. You look at this little face and you realize it's six months old already, and soon it'll be a year and you only get, at best, 90 years in your life," he told ET at the time. "So you look at that little face and you think, 'God, I'm only going to know this person for hopefully 50-55 years.' Suddenly, it doesn't seem like a long time."

Watch Ryan talk more about "loving every second" of fatherhood below!