Paul McCartney and Heather Mills
Lefteris Pitarakis/AP; Kirsty Wigglesworth/AP
She may be the youngest Beatle scion at age 5, but Paul McCartney's daughter Beatrice enjoys grooving to another legendary 1960s rock band.
"She likes the Beach Boys," Beatrice's mother, Heather Mills, told PEOPLE at Saturday's Mercedes-Benz Polo Challenge at Blue Star Jets Field in Bridgehampton, N.Y. Her favorite song to sing? "God Only Knows" from Pet Sounds
, the classic Beach Boys album that traditionally dukes it out with the Beatles' Sgt. Pepper
for the title of greatest album ever
"She's always been into music. It's innate," Mills said. "And she's a great dancer."
Beatrice has been enjoying a nice holiday in the Hamptons, says her mother, and getting a chance to mingle with other kids. "She tried a day at summer camp," Mills said. "All the kids were copying her English accent, which was quite funny."
Mills, 41, who was divorced from Paul McCartney
in 2008, was in Bridgehampton for the Mercedes-Benz Polo Challenge at Blue Star Jets Field. While in the Hamptons, she's also doing some promotion for a new vegan product line of hers.
"Even at lunch today, at the Southampton Beach Club, the people sitting next to me were having cow's milk," she said. "So I said, try soya. It's better for you. And I brought them a little care packet."