Olympia Ohanian is teaching her tennis pro mother Serena Williams a new skill off the court! The Grand Slam champion, 40, spoke about her four year old’s musical talent—playing the piano—during an appearance on Jimmy Kimmel Live! Thursday. When asked how seriously Olympia takes tennis, Serena replied: “She likes it enough.”

“She likes tennis, but I don’t know. Honestly, she likes playing piano,” the tennis star added. “When she was in my belly, I played a lot of like piano music.”

Serena also revealed that her daughter, whom she shares with husband Alexis Ohanian, is taking piano lessons. “And she’s teaching me! Like, I’m not even kidding. I’m like ‘I have a baby Mozart,’” the proud mom said of Olympia. “Of course every parent thinks they have like, a baby Beethoven or whatever.”

Back in September, Serena shared a video of herself and Olympia sitting together at the piano, playing keys. “Sorry!” she says to her daughter in the video, joking, “You gonna fire me?” Serena captioned the adorable post: “I teach her tennis… She teaches me piano… 🎾🎹 @olympiaohanian.”