Presentation of grandmother Meryl.
Actress Mamie Gummer, the iconic girl of the movie, gave birth to a baby boy, the Us Weekly newspaper reported Thursday.
This new family is the first granddaughter of Streep, 69, and her husband, Don Gummer.
The announcement of Mamie's pregnancy, aged 35, was confirmed in December. The star of the "True Detective" has been engaged to Sethi Mehar since August.
Mamie and Streep played side by side in the film "Rickie and The Flash" in 2015.
The actress "Mama Mia!" And Don share three other children; Henry Wolfe Gummer, 39; Grace Gummer, 32, and Louisa Gummer, 27.
A Gummer representative did not immediately respond to our request for comment.