A Night Time Mystery....

Sooooo, Greg goes in to wake up Luke for school this morning. To Greg's surprise he noticed Luke's pajama shirt was different then when he went to bed last night...As Luke mosied out of bed, both Greg and Luke not only noticed that he was missing his pajama bottoms, but was butt naked from the waist down! Puzzled, Greg tells Luke to get dressed for school and leaves the room. Not a minute later, Luke arrives in our bedroom and says, "Look Daddy." He shows Greg that he still had the pajama top on from the night before under the new one. Luke has no idea how this happened. Do we have a sleep walker on our hands?!? I do recall hearing him have quite the conversation in his sleep last night!!