Gummer, 32, plays the daughter of Streep's rock star character in the upcoming film "Ricki and the Flash", reported People magazine.
"She's brave and fearless and funny and free. She's a free talent. It doesn't have any cover up - she's the real deal," Streep, 66, said during the world premiere of "Ricki and the Flash" earlier this week.
In the film, the pair struggle through a strained relationship with Gummer's character blaming her mother for putting her music career before her family. But in real life, Gummer said she does not want to hurt Streep.