Which Bed Part 3

After I put Ben to bed tonight, I heard a bunch of noise up there. I went up there to check on him. He went into our room and was climbing into our bed. I told him to go back to his room and shut the door. He did and he is now sleeping in there. The crib is not good enough for him, his toddler bed is not good for him and does this mean that the twin bed is not good enough for him either? He really wants to be a big boy.