Forget their famous mom, Brooke Shields' young daughters’ favorite celebrity is red-hot pop star Katy Perry. “They love her songs. They know all the lyrics,” Brooke told In Touch about 7-year-old Rowan and 4-year-old Grier at the grand opening of the JW Marriott Marquis in Miami on November 4. Though she calls Katy “sweet,” the actress is uneasy about her girls’ sexy role model. “They’re so young, so that makes me a little bit nervous. I mean, bikinis and daisy dukes?” Brooke added, referring to a line in Katy’s hit summer single, “California Gurls.” Brooke isn’t the only mother who thinks Katy could be too hot for tots -- Sesame Street recently pulled the singer’s debut on the iconic children’s show after parents complained about her cleavage-baring outfit.