Britney Spears' exes go to war as Kevin Federline comments on Sam Asghari's jab

Kevin Federline fired back at Sam Asghari after Britney's most recent ex took a swipe at him while discussing Federline's upcoming memoir You Thought You Knew. Sam didn't hold back when asked about the project in August, sneering, 'Well, he was a professional father so he would be a great... it would be the first book that'll tell you how to be a professional father.'