The 49-year-old star, who has become a father for the third time, also has a son, Indio, from his previous marriage.
Last Thursday, The Judge star, 49, paid a loving tribute to his pregnant wife and soon-to-be-born daughter during the BAFTA Los Angeles Jaguar Britannia Awards, where he received the Stanley Kubrick Britannia Award for Excellence in Film.
"It's just the uncertainty of how nowadays you have all these things where you think you have much more of an understanding of what you're going to get," said the Iron Man star.
He added, "And then this little soul lets herself be known to you, and it's just like: You don't know anything. It's great!" In his acceptance speech at BAFTA Jaguar Britannia Awards, Robert Downey Jr. asked his wife to stand up and said, "How is she still so darn pretty and functional and mood-stable?" He even joked, "the second pregnancy has been extraordinarily tough for me. Self-prescribed mandatory bed rest was of some benefit. At least my milk is finally coming in."
However, Robert Downey Jr.'s rep has not yet confirmed the news. We are really happy for the handsome star who has become a proud father of 3 kids!