Jose Fernandez's daughter was born on Friday, according to Clark Spencer of the Miami Herald.
Fernandez's girlfriend, Maria Arias, gave birth to a baby girl named Penelope. The name was picked out shortly after the couple discovered the baby's sex.
Fernandez died a month later in a tragic boating accident. He was 24 years old.
At Fernandez's funeral, his agent Scott Boras mentioned the young pitcher's excitement to become a father.
• Jose Fernandez's death hit hard for the Marlins, baseball and Cuban-Americans
"He wanted to know, am I going to be a good father?