That's because with a baby blue bat, Harper revealed to the fans in the stadium -- and all around the world -- that the baby he is expecting with his wife, Kayla, will be a boy. They're having a boy!

Bryce Harper is set to take another swing at fatherhood — and he did it with a blue bat. The Philadelphia Phillies slugger used a blue bat in his first plate appearance of Monday night's game ...

Bryce Harper is set to take another swing at fatherhood — and he did it with a blue bat. The Philadelphia Phillies slugger used a blue bat in his first plate appearance of Monday night’s game against ...

Philadelphia Phillies superstar first baseman and right fielder Bryce Harper found out the gender of his upcoming fourth ...

Pink and blue bats are normally reserved for Mother's and Father's Day in the major leagues, but Monday marked an exception. Philadelphia Phillies outfielder Bryce Harper is expecting his fourth ...

PHILADELPHIA — Bryce Harper is set to take another swing at fatherhood — and he did it with a blue bat. The Philadelphia Phillies slugger used a blue bat in his first plate appearance of ...

Bryce Harper ... and he did it with a blue bat PHILADELPHIA -- Bryce Harper is set to take another swing at fatherhood — and he did it with a blue bat. The Philadelphia Phillies slugger used ...

“It’s a boy” - Phillies’ Bryce Harper’s swings a special blue bat for an emotional gender reveal for fourth baby (Image Source: Instagram) His teammate, Trea Turner, praised the idea of ...