A gift for WifeyMcWiferson, based on an incident she told me about her son.
In retrospect, even Sam had to admit the prank war was completely his fault, even if he had, inadvertently mind you, started it.
It's not like he meant to accidentally put salt in the sugar canister. It's not like he wanted his brother to bite into a painfully salty apple pie, resulting in Dean upending his mug of scalding hot coffee into his lap which then resulted in Dean tumbling out of his chair and smacking his head on the Batcave's war table.
In fact, it was such a solid prank that Sam sorta wished he had done it on purpose.
He knew Dean was going to get him back, and he knew it would be epic. So for days after the pie incident, Sam walked around the Batcave like the floor was made of egg shells. It's not that he was really afraid of Dean, but his brother definitely had an evil genius streak that was cause for concern.
Sam was very careful with his toiletries, trying to avoid the Nair shampoo incident again. He took to locking his bedroom door at all times. He was getting more paranoid by the minute, but still, Dean did nothing.
In fact, two weeks went by, and Sam relaxed so much, he actually forgot that Dean still "owed him one".
That all changed one sunny Thursday.
Bob the Builder! "CAN WE FIX IT?" Bob the Builder! "YES WE CAN!"
Sam could hear Dean singing along to the children's show from where he was currently shaving in the bathroom. He wasn't exactly being quiet.
He found Dean on the couch, surrounded by stuffed animals, action figures, a "Cars" fleece blanket, a bazillion pillows, a large box of goldfish crackers, and a pile of children's books. "Bob the Builder" was on the TV, but that wasn't even the most disturbing thing about the unusual scene.
Dean was, completely and totally, naked.
He was laying upside down on the couch, head tipped over the edge, bare legs up over the back cushions.
"Dude. What. The. Hell."
"Howdy, Sammy!" Dean said with a huge grin, waving from his odd position on the sofa.
"What the hell are you doing? Why are you…naked?" Sam asked, averting his eyes.
"New rule, Sammy. Thursdays are officially Naked Toddler Thursdays! I get to watch kids' shows, lay around on the couch eating goldfish, and in general, annoy my now older brother. I am four. This is the last coherent adult statement you'll get from me today Sasquatch." Dean narrowed his eyes and stuck his tongue out at Sam.
"Why naked?" Sam asked wearily, belatedly wondering why that was the only thing worrying him about Naked Toddler Thursdays.
"'Cause clothes are stupid!" Dean yelled as he threw a handful of goldfish at Sam.
"Oh, real mature, Dean," Sam huffed.
"I KNOW YOU ARE BUT WHAT AM I?" Dean hollered at the top of his lungs. He grinned at Sam, and started hurling stuffed animals at his brother. "ANIMAL WAR!" he screamed, and Sam brought his arms up to protect himself from the onslaught.
"Dean! This is the stupidest thing you've ever done!" Sam started throwing the stuffed animals back at Dean. "Where the hell did all these fucking things come from anyway?"
"OOOOH! SAMMY SAID A BAD WORD!"
"Oh, this is ridiculous. I said I was sorry about the salt thing, dammit, Dean!"
"ANOTHER BAD WORD! BAD SAMMY!" Dean's pulled himself to his feet and is now bouncing up and down on the couch in all his naked glory, grinning like, well, like a little kid.
"Jesus Christ, Dean," Sam puts his hands over his eyes, "this is why people like Becky write all the crazy Sam slash Dean crap!" Sam turns away and heads out of the library, intent on hiding in his room for the rest of Naked Toddler Thursday, when there's an almighty crash and a groan from behind him.
"Dean?" He turns, doesn't see Dean anywhere, so he walks back towards the couch to find Dean sprawled on the floor, long limbs covered in pillows, stuffed animals, and goldfish.
"Ow," he groans.
"Dean fell off the couch," Dean replies sulkily. "Dean got an owie."
"Dean needs to stop talking about himself in third person."
"Yeah. Maybe Naked Toddler Thursdays were a bad idea."
"Aw. Did widdle Deanie hurt his widdle head?"
"AWWW, wook widdle Deanie is all hurt and grumpy. Widdle Deanie needs a nap."
Dean glares daggers at Sam as he yanks his boxers out from under the couch and yanks them on. He starts grumpily cleaning up the mess.
Glaring at him a second more, Dean's face finally relaxes, and he mutters "truce" then resumes clean up, Sam kneeling to help him.
They're almost done, when Dean looks up again, mischief in his eyes and says,
"Yeah, truce…at least until Stripper Pole Saturday!"