Disclaimer: Much as I would love to take them all home with me (Dean in particular) I can't so in my dreams I borrow them just for a little while and there is no money coming my way from this temporary loan.
Summary: A one-shot about Dean as he grows up: my take on why Dean is like he is.
When he was little, Dean had loved to watch his mum as she looked after his brother. When she died, he knew how to love his brother with all his heart, just as his mum had done.
When his mum died, Dean worried that his dad would go too, so he watched him. He watched him look after his brother.
The first time his dad was late home from a hunt, his brother was okay because Dean knew what to feed him and when it was time for bed.
When his dad was late home the first time, Dean was worried. He worried that his dad wasn't coming back and he worried that he didn't know all he needed to, to look after his brother, so when his dad came back. Dean watched even more carefully, frightened of missing something important in how to look after Sammy. He still worried about his dad but more important was Sammy because the first thing Dean had learnt to do was to love his brother.
When his dad didn't come home for three days, Dean made sure Sammy was clean, fed and sleeping. He got him to school on time, he worried about his dad but Sammy was okay. On the third day, he knew the fridge was almost empty and he didn't have money for any more food. He worried about how he was going to keep feeding Sammy. He skipped breakfast to make sure there was something for Sammy to eat in the evening and he hoped his dad would come back. That night his dad came home, so he didn't need to worry about running out of food to eat, instead he worried about the next time his dad didn't come home.
Dean started watching to see how people made money just in case… He watched guys play pool for cash in bars where his dad talked to contacts. He watched kids run errands for people in the neighbourhood. He watched waiters and waitresses spend long hours trudging between kitchens and customers while his dad read newspapers and Sammy played with his power rangers. Dean watched guys play poker and in one particularly grim bar, Dean went to the bathroom and saw a male whore doing business. Dean knew the safest job didn't pay the best money and so figured he could start saving now.
The next time, his dad checked into a motel for more than a couple of days, Dean talked the owner into letting him do odd jobs in exchange for cash. He hid the money he made in the pair of shoes he wasn't wearing.
Sometimes when they hadn't got anywhere to stay yet or were moving on as soon as a job had finished, John Winchester would take Dean and Sammy with him when he went hunting. Dean would watch over Sammy in the car and keep him safe just like his dad told him too. Then one night, the monster got past his dad and tried to get at them and Dean realised being in the car wasn't always going to be safe enough. By the time, the monster had broken through the window, Dean had Sammy behind him and was able to kick it in the face before it grabbed his leg and tried to pull him through the window. A shot rang out, his dad was there and the monster was dead. It hadn't mattered which monster it was because Dean had almost expected that he was going to let Sammy down some time, it wouldn't happen again. He realised he hadn't watched his dad closely enough for him to be trusted with looking after Sammy.
That night when Sammy was asleep and his dad was cleaning the gash on his leg where the monster had grabbed him, Dean asked his dad to teach him about guns and knives and so he started to learn how to protect Sammy.
Dean knew that now he could protect Sammy, so he watched everyone and everything to make sure nothing could hurt Sammy.
When Dean was 22 and Sammy was 18, Sammy left. Dean realised he had been so intent on watching everything to keep Sammy safe, that he hadn't watched Sammy grow up and change. He'd missed the signs that Sammy didn't want or need him anymore and now it was too late. Sammy had gone.