Childhood
To be honest, Sam Winchester hated his childhood. It was full of constant moving, fear, and an anger towards his father. Now that he thought about it, though, not all of that anger at John was completely deserved.
For eight years he was in the dark about his dad's job, about why his father would come home covered in blood. He didn't know why his mother was gone. All he had to depend on was his brother, Dean. He didn't have a dog, or even a house. Then again, did he really need any of that when he had a family?