Agnes apparently had enough of waiting when Mary openly started putting up sigils and other markings that were more effective than a standard cross when dealing with a potential demon.
Crosses could be inverted with ease. Yes, they could cause pain to a demon, but in reality salt and iron were better deterrents for them when they were incorporeal like Agnes was. The same day Sam dumped a few crucifixes into the water supply for the house, Agnes immediately possessed Dean the second he left the shower.
Dean didn't stand a chance...he had taken off the amulet to prevent demon possession to take a shower, and Agnes was already agitated by the fact Sam knew how to deal with demons.
Things turned worse in mere days. Agnes was clearly trying to take control over Dean's soul, but she evidently didn't realize she was dealing with the most stubborn bastard on the planet. Add on top of that the fact that Dean was the vessel for Micheal, and Sam was counting on some divine intervention if things got too bad.
Seeing the demon using Dean as a meat suit really pissed him off, but due to safety concerns his mother had sent him out before the priest she knew started the exorcism to get the demon out. While any hunter knew the words, Mary thought having the extra power of a priest doing it would insure Dean's survival.
Sam watched from outside, but inwardly he was worried for Dean. So when he saw the exorcism go from bad to worse to potentially deadly, he knew he had to do something.
He was still terrified of revealing the truth about him being an angel, so he decided to call in back-up from someone he knew for a fact could handle a demon like Agnes.
Sam went into his fortified tree house (fortified in the form of markings easily erased) and pulled out something his mother would be very unhappy with if she knew he had it.
A bottle of some old, very expensive liquor and a large quantity of quality candy. Mary would likely be a little understanding if he explained why he had stolen it, but Sam would rather not explain it to his mother without giving her something else to worry about more.
Like say, Dean's recovery?
Besides, it was only for an emergency anyway. He never thought he'd need to use it so soon.
Sam set up the circle, sensing that it was only getting worse, and did a speed run when it came to summoning. It wasn't like he could call the being he was after by his real name without sending massive red flags after all.
You could imagine his relief when the Trickster Loki appeared.
"Well you got my attention kid. Where did you get the 60 year old bourbon though?"
"Please save my brother!" said Sam quickly, before he absently added "And I stole the bourbon from the local shop. It was overpriced anyway."
Loki blinked.
It was then he took notice of where he was...more specifically what was going on inside the house. The flying furniture and people shouting Latin was a pretty big give away.
"...You do realize I'm a trickster god and a pagan, right?" said Loki slowly.
Sam gave him a deadpan look.
"You're also older than the witch turned demon is, and I'm betting you have your own way of dealing with demons without killing the host. Besides, none of your legends mention you targeting kids," said Sam flatly.
"And why should I humor you?" asked Loki, though Sam knew from previous experience he was considering it.
Sam held up a large box filled with expensive candy.
Loki didn't bother asking where Sam got the candy. Instead he walked into the house as calm as you please, with Sam joining him.
Mary was clearly devastated, the priest was having absolutely zero effect, and Dean was looking worse for wear.
His mother was visibly upset seeing Sam, and utterly dumbfounded when the stranger her son was with walk past the salt line, touch Dean's head...and a flash of light filled the house.
The demon's enraged shriek was audible, as was the pain-filled one soon after.
"Sam?"
Loki caught Dean easily enough. The poor kid looked like hell...but his soul was intact and the demon was most certainly dealt with permanently.
Sam silently handed Loki the large bag of quality candy without a word, before going to check on Dean.
"Sam, who is this?" asked Mary.
"Loki, the trickster," said Sam, relieved his brother was alright. Maybe a little drained spiritually and physically, but he would survive.
Mary went stiff. The priest, however, frowned.
"Why is a trickster here?" he demanded.
Sam gave him a flat look.
"I really doubt we're the first ones to try an exorcism on the demon here. So I decided it was a good idea to call in someone who's been around longer and doesn't have any legends to indicate they specifically harm children. Loki might be a trickster, but all the stories indicate he only goes after the overly spoiled children who need an ego check."
While the house was now demon and ghost free, the family had had enough of the place. There was still too much negative energy in the place, though Sam discreetly turned house into blessed grounds before they moved out.
Loki knew something was up with the kid who summoned him. He was far too sure of the pagan's assistance in dealing with the demon. And his eyes...they felt too old. More importantly was the warding on his body.
Curiosity piqued, Loki waited until Sam was alone before he reappeared in front of him.
Sam was startled, but not overly alarmed.
"You know for the son of a hunter, you're way too calm about a trickster spirit around with no protection."
"If you actually were a trickster, I would be worried. However I know something other hunters don't," said Sam.
"And what's that?" said Loki, snapping up a candy bar.
"Your real identity. I have to admit, going pagan as a form of witness protection was complete genius. Particularly since your siblings are less than enthusiastic about other 'gods'."
"Oh? And what sort of family am I from?" asked Loki, though inwardly he was starting to worry.
Sam's expression said volumes.
Loki started to actually worry more.
"Gabriel, the archangel and the one who spread the word of god...particularly the appearance of Jesus to the masses."
Loki, or rather Gabriel, attempted to laugh it off.
"Nice try kiddo," said Gabriel.
Sam wasn't finished though.
"You left heaven because you were tired of the fighting, particular between Micheal and Lucifer and decided to go pagan as a sort of witness protection."
Gabriel took the kid seriously now.
"Who are you?" he asked suspiciously.
Sam briefly flared his wings. It had taken a bit of getting used to, and he rarely let them out properly for obvious reasons.
Gabriel's expression was priceless.
"My name is Sam Campbell, formerly Winchester. I'm supposed to be Lucifer's vessel once the apocalypse starts," said Sam bluntly. "Though I hopefully screwed up that plan when I sent that damn Azazel to heaven before he could infect me."
Gabriel's minor panic attack latched on to one important piece of information.
"Wait...the sudden influx of demons in the deepest parts of heaven...that was you?" said Gabriel.
Sam averted his eyes from Gabriel's face. Gabriel started howling.
"Dear father, that's hilarious! Do you have any idea how much bitching I've been overhearing for the past couple of years because they have no idea how those demons kept ending up in heaven?" said Gabriel cackling.
"It's not like I can do anything else! I woke up as a baby without any warning at all, complete with my recently gained grace!" said Sam flushing, embarrassed. "Cas was only able to teach me a few things before it happened!"
"Cas?" asked Gabriel.
"Castiel."
Gabriel was highly amused. Castiel was a foot soldier as far as he knew, so the amount of things he could teach what could only be a fledgling...the first since Castiel's generation at least...was highly limited.
Besides, this kid clearly had the sort of humor Gabriel really wanted to encourage. Anyone sneaky enough to send demons to the deepest part of heaven was his kind of angel.
Gabriel ruffled Sam's hair, which caused the baby fledgling to scowl like an adult.
When Mary and Dean returned, Gabriel was long gone. But Sam had little doubt the bored archangel would be back.
In a weird way, it felt like coming home when they arrived at Bobby's house.
Mary felt only relief after the harrowing mess at their former home. Fortunately, Sam knew Bobby was only gruff on the outside.
Dean and Mary kept an eye on Sam, and when he showed nothing but calm while in the house, they relaxed. Considering he had picked up on the demon in their last home, this reaction was understandable.
Sam made a beeline for the panic room in the basement, with Dean following him after a moment's thought, and promptly crashed on the rather small bed in the room. Bobby didn't say a word, considering what the kids had been through. He did wonder how Sam knew about his demon-proof panic room.
A few weeks later...
Mary was relieved when she realized that Sam and Dean were recovering from their ordeal. She still didn't know how or why Loki of all creatures seemed to find it amusing to drop in on her youngest.
Considering he had saved the life of her oldest son and seemed to be treating Sam as a younger sibling he needed to spoil and possibly corrupt with pranks, she was inclined to let him visit.
Though that was sorely tested when Loki kidnapped Sam for two hours and he came back with an extreme amount of sugary treats, some of them from other countries and exasperated expression on his face.
The only downside to the fact they had essentially moved into Bobby's for the future until Mary found a new place to live was that her sons were introduced to hunting.
Sam was clearly a natural researcher, though Dean was more active. She didn't know where he found it, but Sam had tracked down an amulet that was guaranteed to prevent demon possession.
Something was going on, and it seemed to be targeting her sons.
While she had gotten out of the game years ago to stay by Sam and Dean's side, it hadn't taken much for Mary to get back into the proper swing of things and connect to old family contacts.
Bobby, bless him, had no issue with the boys staying with him while Mary was out of state so that they could continue their schooling.
So when she got wind that something had killed John's new wife Kate and he had barely escaped with his young son Adam, Mary kept an ear out.
Sure enough, it didn't take long for her to hear rumors of someone by the name of Winchester looking into the supernatural.
She had a choice to make. She could let her husband learn everything from scratch...or she could introduce her sons to their half brother and help find out what was targeting her children.
Honestly, it wasn't that hard a decision to make, though it was incredibly awkward being around her ex-husband again.
John looked tired, and who could blame him? He was hunting something that had targeted his family specifically.
He spotted Mary quickly enough.
"Mary."
"John," she replied.
John took one look at his ex-wife and somehow knew. Call it a soldier's intuition.
"You being here isn't a coincidence...is it?"
"Bobby called. Said he heard from someone named Winchester, looking for lore. He pointed me in this direction."
John took a long pull of his beer.
"Mary, I..."
"Don't. The last thing I want is to drag up long forgotten feelings," she said flatly. "I saw report. You and I both know there were no electrical wires anywhere near where her body was."
John tightened his grip on his beer. They had to rewire the nursery before Sam was born, because it had shorted out and the wire had gone back. That was the main reason he had known something was off about the official cause of death, on top of the unknown stranger in the house that night.
"What do you want?"
"Sam and Dean deserve to know their half brother, and you know how protective Dean was of Sam. I know a place where Adam can grow up protected from the thing that killed your wife. However, in exchange you have to listen to what I say during a hunt," said Mary. "This is the only time I'll make this sort of offer, until you're willing to listen to reason."
She didn't know what sort of hold Sam had over the pagan Trickster. All she knew was that Loki had so far shown no signs of aggression towards her sons and that she had even caught him teaching Dean a few protective sigils to protect his baby brother. Sigils Bobby had backed with actual research as legitimate.
She had no issue extending that unofficial protection towards her son's half-brother.
Considering he had been having trouble with Child Protective Service over leaving his young son alone for hours at a time, the offer was highly enticing. Besides, he wanted to see how Sam and Dean were doing, especially after the split.
His decision to leave his youngest with Bobby only solidified at how easily Sam and Dean took to him, and knowing there was a panic room they could escape into inside the house. Adam would be safer at Bobby's while he hunted down the monster that killed Kate.