Britney Spears has added to her family after buying a $3,200 (GBP1,640) puppy gift for baby sons Sean Preston and JAYDEN JAMES. The pop superstar, who is in the middle of divorce proceedings with estranged husband KEVIN FEDERLINE, picked up a pup at pet store Pets of Bel Air during a shopping trip in Los Angeles on Wednesday (10JAN07). Sources claim Spears plans to call her expensive new Chihuahua SNOW WHITE. Meanwhile, the whereabouts of Spears' Chihuahuas LUCKY and BIT BIT and her Maltese LACY, is not known. The dogs were the singer's constant canine companions while she was married to Federline.