K-FED BURIES BRITNEY!

Toxic tell-all says trainwreck ex heading off a cliff

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Federline reveals his fears about Spears in his memoir

HITMAKER Britney Spears is trying to rebuild a relationship with her nowadult sons, but their father - her ex-husband Kevin Federline may not be safe in the presence of the troubled fears the boys pop princess.

"I've been their buffer for years, but now it's bigger than me," Federline writes in his new book, You Thought You Knew. "It's time to sound the alarm." The Oops!... I Did It Again singer, 43, has reconnected with kids Sean Preston, 20, and Jayden James, 19, after not seeing them in person for over three years.