A/N: Written for the spnaufest on Tumblr.

themegalosaurus did some lovely artwork for it, which you can see if you look the story up on AO3 or go to .com.

Beta'd by the lovely liron-aria.

A note on John's characterization: I think that John in canon was an abusive dickhead after Mary died. However, from what we see of him in "In the Beginning" and "The Song Remains the Same", I also think that, in different circumstances, he would have made different choices and been a better person and a better father. I don't think his canon circumstances absolve him of his behavior in canon, not at all, but I think they help explain it. In this story he gets those different circumstances, and he makes those better choices, which is why he's actually nice and likable and a good dad and husband.

Mary runs up the stairs, terrified, panicked, her baby her baby her beautiful baby Sammy there was a man in Sammy's room oh god oh god, but when she gets to the top of the stairs, long-buried instincts kick in. You don't just run into a room containing an unknown monster.

She slows, forces herself to move more lightly on her feet, to move like the hunter she swore she would never be again. And she remembers. Ten years. It has been almost exactly ten years since that night.

She knows what is in Sammy's nursery.

The only salt is in the kitchen. There is no holy water in the house. There is only her, and she remembers all too well how powerful the demon with the yellow eyes is.

She has been edging along the wall towards the doorway to the nursery, and now she reaches it. Slowly, slowly, she leans around to look, Sammy forgive me there's nothing else I can do. The demon stands over Sam's crib. It looks like it's holding its hand out, over Sam. It murmurs something, too soft for her to hear, reaches down and strokes Sam's head no not my baby get your filthy demon hands off my baby but she has to stay still or leave her boys without a mother and she will not do that to them, and then the demon is gone. Vanished.

And Mary is across the room in an instant, running her hands over Sam, even though she doubts the demon did anything so obvious as physical injury. Finding nothing, she scoops him up into her arms, holding him close, and it is all too much, too much and she sinks to the floor with a quiet, strangled sob.

The next day she begins searching the yellow pages as soon as John leaves for the garage. She has to know she has to know what the demon did to her baby, has to know what to do oh god this was not supposed to be her life; focus Mary you chose this ten years ago now woman up your baby needs you.

She gets that little buzz of intuition when she reads Missouri Moseley's ad, so she calls the number.

The woman agrees to come over, and Mary learns her instinct was right. But Missouri can tell Mary little that she does not already know or has not already guessed: something evil came to her house, and it left something of itself behind, inside Sam.

Mary makes them tea, hands shaking, mind overflowing with doubt and confusion and I don't know what to do.

But Missouri is very good at her job. She talks Mary down, gives her the numbers of her contacts in the psychic and hunting communities, tells Mary to call any time. Mary is so, so grateful, but she doesn't understand why Missouri would go to the trouble.

Missouri looks her in the eye and says, "First, 'cause you're payin' me. Second, 'cause I don't want no evil movin' into this town and causin' trouble, seein' as I live here, too." She has a fierce, determined look that Mary recognizes.

Mary smiles. It's good to have an ally.

That's how it begins. For weeks, Mary spends all the time not devoted to Sam and Dean and running the house and being John's wife while keeping him in the dark for now, it's just for now, can't risk him not believing me doing research. She digs her parents' things out of the basement and starts calling and writing old contacts, as well as the new ones Missouri gave her, asking if anyone has ever heard anything, anything at all, about a demon with yellow eyes, a demon who makes deals but not for souls, a demon who visits babies but doesn't take them or hurt them in obvious ways. She tracks down the others, the ones who made deals at the same time she did. They all have babies about Sam's age. One of them died in a freak fire. She contacts everyone again and asks about fires, too.

She calls and writes universities, pretending to be a student, a reporter, whatever it takes to get experts in mythology and religion and folklore to talk to her. She begins checking out every book of any possible relevance from the library, resisting the urge to skim in her haste, even the tiniest detail could be the one that matters.

She reads, she takes care of her kids, does her best to maintain her home and her marriage she'll tell him she will just not yet she doesn't know how to do it so he'll believe her, and she waits.

In what seems like no time, nearly a year passes. Sam took his first steps, toddling towards Dean as they played. And now her first baby, who isn't really a baby anymore, is going to school.

She has learned a lot in what feels like so little time. She now knows that the older and more powerful the demon, the harder they are to hurt, and Yellow Eyes is probably old and powerful. She put devil's traps on the undersides of doormats at each outer door and on rugs just inside each bedroom. She spent weeks painstakingly filling long, small tubes with salt, attaching them to every window sill, and painting over them so they blend and John won't notice. He's a little bemused by her sudden burst of interior decorating, but smiles and says the place looks great when she's done. She prays he never looks under the mats and rugs, at least not until she's ready for that conversation.

John teases her about embracing the Marines' attitude of being prepared when she fills empty milk jugs with water and stores them around the house; he never saw the crucifixes she used to turn them into holy water.

She continues to collect scraps of information, but feels no closer to an understanding of what happened.

Time passes. Dean graduates from tricycle to training wheels, and Sam inherits the tricycle. Dean discovers comic books, and reads them to Sam. Seeing how much they love tales of heroes fighting monsters, she begins to tell them stories of her life as a hunter. She changes the names and makes all the endings happy, pretends like they are just stories, and her boys listen with wide eyes and enraptured expressions. Dean always wants to know more about the fighting, about how the heroine in her stories took down the monster. Sam is always worried that the heroine will hurt the wrong person, that maybe just because something is a monster doesn't mean it's bad. He likes it best when the heroine wins without fighting, when the solution is a small fire or, better yet, some Latin chanting. He begs her to teach him the exorcism, so she does, relieved that, though he thinks the stories are just stories, three-year-old Sammy will know what to do if a person with eyes all black comes at him. John likes to listen to her stories, too, and after she finishes, he kisses her sweetly and says he never knew she was so talented. He doesn't drink so much anymore, and they're back to trading off cooking and clean-up, and things are good.

One night she hears sniffling from Sam's room as she's on her way to bed. She goes in, walks softly to his bed, and sits down on the edge.

"Sammy?" He emerges from beneath the covers and crawls into her lap, bringing his stuffed toy dog and security blanket with him. He nestles against her, still sniffling, and she takes the blanket and wraps it around his shoulders and holds him close. "Sweetheart, what's wrong? Did you have a nightmare?"

She feels him shake his head, but the sniffles increase to small sobs.

"Shh, baby, shh," she soothes, rocking him gently back and forth. "You know you can tell Mommy anything, right? No matter how bad or silly you think it is, you can tell me. I love you so much, Sam, and I want to help you feel better if I can."

"I'm . . . bad," he gasps out between sobs.

She strokes his hair. "What do you mean? Did you do something you think you shouldn't have?"

"N-no . . . I'm bad," he says, little voice urgent with despair as he tries to get his breathing under control.

"Sammy, love, I still don't understand. Why do you think you're bad?"

"Dean's comic." He's back to sniffles now, trying hard to stop crying.

The three-year-old logic still escapes her. "Dean's comic? One of the ones he read to you?"

"Yes. Gawahad was good, so dey let him go on da special quest. Dere was light and he was good. Dey wouldn't let me go on da special quest betause I'm not good. Gawahad was all cwean inside, but I'm not. I'm bad, Mommy, I'm bad!" And he dissolves into sobs again.

Mary holds him close and strokes his hair and feels her heart break, because she knows there is something bad inside of Sam, and it looks like he can sense it somehow. For long moments she just holds her beautiful, innocent, good little boy, at a loss for what to do, what to say to make it all better when she doesn't understand nearly enough about what the demon did and what it means for Sam. But then her brain draws her attention to her own thoughts, and she thinks she knows what to say.

"Sam, I want you to listen to me very carefully, OK?" She waits as the sobs fade once again to sniffles, and Sam nods his head against her chest. "Whether you're good or bad isn't decided by what you are. If you do mostly good things, you're good. And I know, my sweet little Sammy, that you do mostly good things, and that makes you good."

Sniffle. "It does?"

"Yes, baby, it does. You're good, and I love you, and nothing in the whole universe will ever make me stop loving you, OK?"

There's a silence filled only by Sam's diminishing sniffles. She grabs a tissue from the box on his nightstand and gently wipes the tears and snot from his face.

"I'm good if I do good?" he asks, sounding heartbreakingly hopeful.

"That's right."

"Even if I'm bad inside?"

"Even if there's a part of you that's bad inside."

"And you wuv me for aways?"

"And I love you for always."

He throws his arms around her neck and buries his face in her shoulder, and she holds him tight, and they sit like that.

After a while, Mary hears that Sam's breathing has evened out into the rhythm of sleep, so she gently lays him down and tucks him back into bed, whispering her love into his ear one last time before she leaves the room.