Hollywood Home Wreckers
Britney Spears and Kevin Federline
When the pop star met the back-up dancer in 2004, his girlfriend, Shar Jackson, was pregnant with their second child. Jackson later commented that K-Fed's relationship with the singer "wasn't like just breaking up a relationship -- it was like breaking up a family." The same month his son was born, Spears announced her engagement to Federline after only three months of dating.