P. Diddy has reportedly proposed to his girlfriend, singer Cassandra 'Cassie' Ventura. The rapper is said to be engaged to 21-year-old Cassie, who he met when he signed her up to his music label Bad Boy Records in 2006, but is attempting to keep the news quiet. A source close to the father-of-six told America's Star magazine: "He told everyone to keep it extremely quiet because he didn't want it to get out, but you could tell he was excited. "P. Diddy said they hadn't set a date yet, but he wanted his family to hear the news first." P. Diddy has 19-month-old twin daughters D'Lila and Jessie and 10-year-old son Christian with ex-girlfriend Kim Porter. He also has a son from a previous relationship, a daughter with ex-girlfriend Sarah Chapman and a child he unofficially adopted after ex-girlfriend Kim Porter had a son with her former boyfriend Al B Sure. The 38-year-old star - who has dated Jennifer Lopez and was recently romantically linked to Cameron Diaz - recently revealed he is desperate to work with British singer Leona Lewis. He said: "I want that girl on my next album. I'm a huge fan. Not only is she so, so beautiful, she has a great voice. She is extremely talented. She has one of the best voices I've heard. I'm thinking about my next album and definitely want to make it work, so she's on it. It's all about Leona Lewis."