Britney Spears laughed in the face of new reports she has split from husband Kevin Federline when she joined him for his 28th birthday celebrations in Las Vegas, Nevada. The couple were spotted leaving hip restaurant Tao holding hands on their way to a private party at top club Pure. Spears dressed for the occasion, wearing a sexy black mini-dress. New tabloid reports in the US suggest the couple's tumultuous marriage came to a head recently when Spears kicked Federline out of the beach house they share in Malibu, California.