18-year-old pop star Aaron Carter proposed to his girlfriend in front of about 200 people in Vegas a week ago. But, now he's had a change of heart. Aaron says, "I got caught up in the moment and proposed." He adds, "I then realized it was a hasty thing to do and I am not ready for marriage quite yet."

His fiancee, Kari Ann Peniche, 22, once dated Aaron's older brother, Backstreet Boy Nick Carter. Oh, yes she did. Just when you thought the future Mrs. Carter couldn't be more scandalous, in 2003, she was named Miss Teen USA, but later lost the title after becoming a Playboy Playmate, posing nude in the magazine's November 2004 issue.

The brothers will be featured in their family's upcoming reality series "House of Carters."