Derek Jeter privately welcomes baby no. 4 with wife Hannah Jeter

Derek Jeter knocked this baby announcement out of the park.

The former New York Yankees baseball player announced on May 8 that he and wife Hannah Jeter welcomed their fourth child together, a son named Kaius Green Jeter.

"Welcome to the world lil man!!!" the athlete posted to his Twitter and Instagram pages alongside Kaius' birthday, "5-5-23."

No additional details have been made public at this time but Kaius does share a birthday with his mom, Hannah, who turned 33 on May 5.

Their son joins big sisters Bella Raine, 5, Story Grey, 4, and River Rose, 17 months. And his arrival may not come as a total surprise to many sports fans, as the private couple also kept Hannah's pregnant with River under wraps until she was born.

Earlier this year, Derek shared rare insight into his private life as a dad during an interview.

"The great thing with having kids is regardless of how your day went, most days they're happy to see when you come home," he said. "And that's a great feeling. Regardless of how good or bad your day was, your kids at this age are happy to see you. It doesn't get any better than that."