What went down: Britney Spears started looking more like a home wrecker than a pop princess in 2004 when she fell for backup dancer Kevin Federline. The scandal broke when he walked out on his pregnant girlfriend, Shar Jackson, and their daughter Kori to be with the singer. The pair eventually filmed a reality show, got married and had two children of their own before a major split in 2007. K-Fed manned up in 2010 and apologized to Jackson for his "selfish" ways, during an episode of VH1's "Celebrity Fit Club."
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