Britney Spears' first husband Jason Alexander is ready to reunite with the pop superstar after hearing her two-year marriage to Kevin Federline is over, according to his dad. DENNIS ALEXANDER reveals his son, who spent just 55 hours as Spears' husband at the beginning of 2004, is currently "shopping" a book deal around Los Angeles and he will be offering his ex support as she plans to divorce dancer Federline. Alexander's father tells US TV news show EXTRA, "He's 25 and he's got a mind of his own, but I'm sure he'll be calling her soon." And the man who was briefly Spears' father-in-law insists the pop superstar made a big mistake when she agreed to annul her marriage to his son. He adds, "She could've gone out and done her touring and stuff and Jason could've stayed right here in Kentwood (Louisiana) and looked after things." Alexander insists he always knew the Spears/Federline marriage wouldn't last: "All Kevin saw was a chance to get his hands full. He had that other girl (Shar Jackson) still pregnant when he met Britney."