Serena Williams gives birth to baby girl; sister Venus 'super excited'

Serena Williams has given birth to a baby girl, right in the middle of the US Open. WPBF-25 news producer Chris Shepherd made the announcement on Twitter, citing a source at St. Mary's Medical Center in West Palm Beach, Fla.:

According to CBS12, Serena Williams was officially in labor on Thursday night. The 35-year-old was induced; her hospital floor was cleared and security has been on hand. This is both her and fiancé Alexis Ohanian's first child.

The 23-time Grand Slam champion had said she would wait until delivery to find out the gender of her baby. She has also hinted at a comeback to the tour as soon as the Australian Open, which would give her just over three months to prepare.

Shortly after reports of the birth broke, Venus Williams walked onto Arthur Ashe Stadium to play her third-round match against Maria Sakkari. Just before she did, the 37-year-old was asked by ESPN's Pam Shriver about the news.

"Obviously I'm super excited," Venus said about becoming an aunt. "Words can't describe."

Congratulations for the new parents came on social media, including from fellow players:

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