It's Cher's birthday. The "Believe" singer, who celebrates her 70th birthday Friday, is nothing short of pop royalty. If Madonna is the queen of modern pop, then surely Cher is its founding mother?

There’s the music, the singing, the dancing, the acting—and then there’s the ice cream. Cher talks about Cherlato, her new gelato line, with as much enthusiasm as she does anything else she’s ...