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Serena Williams and husband Alexis Ohanian welcomed their second child, a baby girl, the couple revealed on Instagram Tuesday.

They shared a glimpse of the newborn in an Instagram photo gallery.

“Welcome, Adira River Ohanian,” the 40-year-old girl dad captioned a family photo.

“I’m grateful to report our house is teaming with love: a happy & healthy newborn girl and happy & healthy mama. Feeling grateful. @serenawilliams you’ve now given me another incomparable gift — you’re the GMOAT,” he wrote.

Serena and Alexis were married in 2017. They share 5-year-old daughter Alexis Olympia Ohanian, Jr.

“Thanks to all the amazing medical staff who took care of my wife & our daughter I’ll never forget the moment I introduced @olympiaohanian to her baby sister,” Alexis wrote on Instagram.

He concluded his post: “Your peace would have been like a river, your well-being like the waves of the sea.”