R&B singer Alicia Keys and her husband, music producer and rapper Swizz Beatz, have welcomed their second child.

"The joy of joy is joy!! It's a boy!! We are so grateful!! #blessings!!" the two posted simultaneously on their respective Twitter pages Sunday. Each linked to an Instagram page with a photo of baby footprints on what appeared to be a piece of paper or cardboard, specifying that Genesis Ali Dean was born at 1:52 a.m. Saturday, Dec. 27, weighing 6 lbs., 5 oz. Bronx native Swizz Beatz, 36, was born Kasseem Dean.

"Girl on Fire" singer Keys, 33 -- who has won more than a dozen Grammy Awards for performance, writing and other categories -- and Beatz, whose hits as producer include his and Jay Z's "On to the Next One," Chris Brown's "I Can Transform Ya" and Drake's "Fancy," married in 2010 and have a 3-year-old son, Egypt Daoud Dean. Beatz has three children from previous relationships.

The couple had announced on July 31 that Keys was expecting. "Love is life & life is love and we're so excited for another GIFT from up above," Beatz captioned an Instagram photo of himself and Keys, who wore a flowing white gown and cradled her very pregnant belly. "Happy Anniversary my Goddess. 4 years of greatness & cheers to 100 plus more inshallah," he added, using the Arabic word for "If Allah wills" or "God willing."

Shortly after that, Keys posted a slightly different image from the same session, captioned "Happy Anniversary to the love of my life . . . And to make it even sweeter we've been blessed with another angel on the way!! You make me happier than I have ever known! Here's to many many more years of the best parts of life!"

Beatz is also a Grammy-winner, having shared with Jay Z the 2010 statuette for Best Rap Performance by a Duo or Group, for "On to the Next One."