KFEDERLINE081307_01.jpgKFEDERLINE081307_04.jpgKevin Federline KFEDERLINE081307_07.jpgAs Kevin wages an all-out war on his ex over the custody of their kids, you think he might be a little more careful who he lets around his sons! X17 photogs caught this mystery blonde leaving Kevin's Tarzana house on Sunday afternoon (the day he had the boys). We're working on an ID. I guess it's possible she could be some sort of nanny, assistant - but in that short skirt? That would be indecent exposure!