Tennis superstar Serena Williams has become a mother for the second time. The 41-year-old shared a photo of the infant with her, her husband Alexis Ohanian and their first daughter Alexis Olympia on Instagram. In the caption, Williams revealed the second child’s name: “Adira River Ohanian.”

Ohanian posted more pictures. “Serena Williams, you have now given me another gift beyond compare, you are now the GMOAT,” he wrote, short for “Greatest Mother of All Time.” “I will never forget the moment I had the privilege of introducing Olympia Ohanian to her baby sister,” added Ohanian.

With 23 singles titles in Grand Slam tournaments and 319 weeks at number one in the world rankings, Williams is considered one of the most successful players of all time.