That is not why they upgraded you. Every 2br at Saratoga is made up of a 1BR and studio with a door between them that locks them off. There are no dedicated 1or 2BR units. They upgraded you to be nice because the connecting studio was not booked. By definition, if they have a 2BR, they have a 1BR.
How small is she? They make smaller inflatable kid beds. I know that All Star Music and the Port Orleans have a curtain between the dressing area and the room. You could set up that bed on the floor in the "closet" area and pull the curtain closed. She'd be up against a wall and the sink, it would have the light from the hair dryer for a nightlight in there too. But if you need to go to the bathroom, you'll have to walk past her.