I feel for you dude!
Had the same thing happen at my brothers house. They removed a paving slab, threw it through the kitchen window and climbed in, to go through my mums hand bag (looking for the keys of my brothers BMW). When he woke and ran down stairs they told him to go back to bed before someone got hurt... Thankfully they didnt get the keys as they were upstairs! And even left my mums creditcards in the garden for her.
So remember.. its not just about leaving a nice car on the driveway.. hide bags as well as keys!!