Federline's parents – Mike, an auto mechanic, and Julie, a bank teller – split when Federline is 8 years old. Federline resides with his mother and brother, Chris, until he is 10 when the two brothers move with their father to Fresno, Calif.
In the ninth grade, Federline drops out of high school, and begins dancing with the non-profit organization, Dance Empowerment. After delivering pizzas for a living and getting his GED, Federline moves to L.A. to pursue dance professionally. He shares a one-bedroom apartment in Hollywood with six people, and becomes known as "the dirt cat" in the dance circuit because of his grungy look. During the next few years, he tours as a back-up dancer and dances in music videos for Justin Timberlake, Pink, Destiny's Child, and Michael Jackson. "There's nobody that gets less credit than somebody dancing," Federline tells PEOPLE.
Federline begins dating Moesha actress Shar Jackson. In July 2002, the couple welcomes their first child together, a daughter Kori. "I always wanted to be a young dad," Federline tells Details in 2005. "I didn't know if I was going to be with the mother forever, but I knew whenever I did have children, I was going to love them more than anything." In the winter of 2003, Jackson becomes pregnant with Federline's second child.
Out with friends during a break from her tour, Britney Spears spots Federline at Hollywood club Joseph's. The two begin dating, but Federline's girlfriend Jackson is six months pregnant with their second child together. After Spears and Federline are photographed leaving the Beverly Hills Hotel together, Federline leaves Jackson for Spears. He accompanies the pop star on her international tour. ''This just isn't right,'' Jackson tells PEOPLE. "This is a big thing. It isn't like breaking up a relationship, it's like breaking up a family." Federline tells the Associated Press that he never expected falling in love with Spears. "It was one of those love-at-first-sight type deals."
After a three-month, paparazzi-packed courtship, Spears indirectly asks Federline to marry her while on a plane to New York from Ireland. He declines but minutes later he asks her, and she accepts. "My head was spinning. Oh my God, I was happy," Federline tells PEOPLE in July. "I wasn't really thinking about asking her right away but I did without reservation. I'd known for a while that she's the one."
Federline and Spears marry in a surprise ceremony at a private home in Studio City, Calif. The wedding is planned for Oct. 16, but as press attention grows, the couple invites 27 friends and family members to what they pretend is an engagement party. "From the day we got together, she has always been there for me," Federline tells Details. "I mean she's f---ing proud of me. I could be sitting at home doing nothing…She's more proud of me than anyone has ever, ever, ever, ever been in my lifetime. Ever."
Men's style magazine Details gets Federline to swap his baseball hat, baggy jeans and T-shirt for a more sophisticated look. "This is to let people get to see the real me," Federline says. When he is asked to comment on the media frenzy surrounding his leaving pregnant girlfriend Shar Jackson for Spears, he says: "They can say I'm a bad father. They can say I cheated…But I know, and that's all that matters. If my daughter was here right now, you'd be able to tell by the look on her face that I'm the best damn dad in the world."
The couple's reality show Britney & Kevin: Chaotic debuts on the UPN channel. The show chronicles the beginning of the couple's relationship, but it barely causes a blip in the Nielsen ratings. Federline tells Teen People that the project is a "documentation of love."
Spears gives birth to son Sean Preston by C-section. The following September, the couple welcomes a second son Jayden James. Federline tells PEOPLE that with each birth, "it gets less and less stressful," but fatherhood has made him restless. "It's just time to get my stuff down while they're young, so I can sit back and watch them grow up."
Spears agrees to a Dateline interview with Matt Lauer while pregnant with her second child. She disputes marital problems, calling her marriage "awesome," and says of Federline, "He cares so much, and his heart is awesome. He has a really big heart, and I love that."
BIOGRAPHY (top to bottom): Splash News; Splash News; London Entertainment/Splash News, inset: Jill Johnson/JPI; Courtesy of Details Magazine; CBS