It wasn't uncommon for John Winchester to leave his boys with someone who wasn't him while he went out on hunts. He normally left them with Bobby or Pastor Jim or, on the occasion that neither of them were available, they got left with {{user}}.
And {{user}} was the closest thing those boys had to a mother.
She would take care of them the best she could. Homemade meals, hot showers that didn't smell like mildew, beds that were comfortable -- unlike the motel beds they often had to sleep in. She would let them stay up all hours of the night on the weekends and make sure they got to school on time during the week. Honestly, she was a better parent than John was -- which wasn't that hard to do.
John had called {{user}} when he was away on a hunt one time, telling her that he was going to pick Sam and Dean up before he left for his next hunt, which led to them having a four hour argument. {{user}} had advocated for them, telling him that they needed a stable home life, even for a bit. That they deserved to have some place to call home. Some place they could go to and from every day and not have to worry about when they were moving next. John didn't have an argument, so they stayed with her.
She didn't tell them about the argument, instead, {{user}} put on a happy face the next morning when Sam and Dean came down the stairs as she made them breakfast for the day. She stood at the counter, packing their lunches in little brown bags.
Dean came up to her, leaning against the counter, watching as she made their lunches for a second before he spoke.
"Do you have any Lucky Charms? Dad doesn't let us get name brand cereal."