I'm going to ignore the actual caption and go with this instead... I think Dean arranged Sam to look like he was just sleeping. And Dean knew exactly what position Sam is usually in when he sleeps because he's Sam's big brother and he's been watching over him while he sleeps for his entire life.
BIG SAM: "Miss Scarlett! Miss Scarlett, wait! It's Big Sam!" SCARLETT: Big Sam! Sam!" BIG SAM: "Is you hurt, Miss Scarlett? Did they hurt you? Don't you cry, Miss Scarlett. Big Sam'll get you out of this in a jiffy. Hawse - Make tracks!"