Teen star RYAN CABRERA is officially dating Elvis Presley's model granddaughter RILEY KEOUGH, just two weeks after ditching his most recent squeeze. Cabrera, 24, has been linked with Keough - whose mother is Lisa Marie Presley since splitting with The Veronicas singer LISA ORIGLIASSO earlier this month (JUL06). Confirmation was provided when the pair stepped out to celebrate Cabrera's 24th birthday at New York nightspot the Plumm together, reports the New York Daily News. They were also joined by guests including Jesse Metcalfe and Cabrera's manager Joe Simpson, the father of his former girlfriend ASHLEE SIMPSON.