Sam grinned at the dopey look on Dean's face and the typical bewildered expression on Cas's. They both looked completely ridiculous, staring at each other from across the table.

"Swimming?" Cas repeated, playing with the word like it was in a different language. Sam chuckled, and Cas shot him an accusing and very human look. It was still so new, seeing him act like that, and Sam knew it would be years before he got used to it.

"Yeah," Dean said, leaning back in his chair. "You know, water? You can't say that in your entire life you haven't once gone swimming." When Cas didn't answer, Dean ran a hand through his hair and groaned. "Seriously? You've been around, what, a few million years? Never?"

Cas shook his head and studied the tabletop with the same intensity that he used to look at everyone when he was still an angel. Sam's eyes darted between the two, and he smiled again.

"I guess it's up to us to teach him, right?" he asked, elbowing Dean in the side. Dean glanced at him, the goofy look on his face fading a bit. Sam couldn't tell, but it looked like there was some kind of understanding there. They nodded at each other and fixed Cas with a very maniacal stare—the kind that only plotting brothers could do.

"We're teaching you to swim," Dean said with finality, getting up. He downed the last of his coffee and headed up the stairs, toward the area of the bunker where the bedrooms were. When he disappeared, Cas heaved a sigh.

"Are you really going to make me do this?" he asked helplessly, begging Sam with his eyes to make it not true.

Before Sam could respond, Dean shouted from his bedroom, "Shit, man, we've gotta get Cas swimming trunks!"

Cas flinched, and Sam burst out laughing. "Does that answer your question?"

When Cas stepped out of his bedroom, Dean started laughing heartily, shaking his head. Sam's lips quirked up, and he sniggered at Cas's confused, shy expression. The swimming trunks Dean lent him looked far too big, and they made Cas look like an oversized teenager.

"You're not supposed to wear it over underwear," Sam said gently. Dean was still laughing, and he hadn't even thought to tell Cas what was so funny. Sam knew Dean found it endearing, but he didn't know how to teach somebody these kinds of things yet. They were going to have to get used to that, too.

Cas glanced down at the band of his boxers, clearly showing over the waist of the trunks. He blushed and ducked back into the bedroom, closing the door softly behind him.

"This is so weird," Dean said, shaking his head.

"Yeah. I know."

There was a muffled bump from behind the door, and both of them laughed quietly again.

"It's gonna take him a while to get used to all of this, isn't it?"

Sam nodded and rocked back and forth on his heels. A glance at his brother told him that that question wasn't directed at him. Dean was just thinking aloud. He never used to do that before. He never got that faraway look in his eyes before, either. Since Cas had made the bunker his permanent home, Dean did both of those things quite a lot.

Cas opened the door again, and Sam heard Dean snort quietly. Of course, he could see why. The swimming trunks were too big for Cas, and they were slung dangerously low on his hips. Sam suddenly found the crack in the ceiling very interesting, and directed all of his attention there.

"Is this right, now?" Cas asked.

From the corner of his eye, Sam could see Dean shake his head. "There's a drawstring on the inside. They're, uh, a bit loose. Don't want you to lose them." There was a rustling of fabric, and Sam assumed that Cas had found the drawstring himself. There was a beat of heavy silence, and Sam looked back at the two of them. Each was studying the other's shoes, and Dean looked like he was trying to find something sarcastic or witty to say. Obviously, it wasn't working.

I know him too well, sometimes, Sam thought as he wordlessly bowed out. He guessed that Dean would eventually figure he had to get changed, too.

It didn't take long for them to find a usable lake. They circled the area around the bunker for about a half hour before anything that looked promising turned up. It was surrounded by soft looking pine trees, and there was a narrow beach running around the whole thing. There was nobody around except a man in a little boat at the other end of the lake. Sunlight was slanting off the surface of the water, blinding Sam momentarily.

Dean jumped out of the Impala the second the engine was off. Sam and Cas followed more slowly, Cas eyeing the water like it was lava and Sam breathing in the fresh smell of the woods.

"There's no way to get out of this?" Cas asked, stopping at the edge of the dark sand beach. Dean was at the edge of the water, stripping off his tee shirt. With one carefree glance behind him, he leapt into the water and submerged. He popped up again a few seconds later, his hair plastered to his head and his breath coming out in short pants.

"It's fucking cold in here," he shouted. He went under again and started swimming out in a large loop toward the middle of the lake, heading back toward the beach before long.

"All the more reason not to go," Cas muttered.

"What is it with you and swimming?" Sam asked, pulling off his own shirt. It had been years since he went swimming for fun, and while he didn't love it as much as Dean he was excited. He just wished that Cas was, too.

"I was an angel, Sam," he said. For the first time in a while, Sam could see the deep sadness in those blue eyes that Cas tried to hard to keep hidden. Sam guessed that he did it for Dean's sake, but hiding the pain didn't make it go away. If anyone knew that, it would be the Winchesters. Just another thing to prove that Cas was part of the family.

"What does being an angel have anything to do with swimming?"

"I—"

Sam never had the chance to hear an answer, because before either of them knew what was going on, Dean appeared out of nowhere and started towing Cas toward the edge of the water. Cas protested, but Dean had caught him by surprise. He was able to get the shorter man almost into the water before Cas dug his heels into the sand and stopped him. Sam took a step forward, expecting a sudden outburst of anger or fear. Something along the lines of what Cas was getting at seconds before.

Instead Cas waved a hand at him—even for a human, the guy's senses were good—and frowned deeply at Dean.

"At least let me get my shirt off, first. I don't want to get back into the Impala sopping wet."

Sam expected Dean to kiss him right then and there, but somehow he held himself back. Instead, he stared at Cas like he was Christmas and Halloween and a birthday party all rolled into one. Cas awkwardly pulled the shirt over his head and tossed it to the side, right next to Dean's discarded clothes. Then they both waded out into the water. Cas looked like he was upset and shivering, and Sam noticed the subtle way that Dean grabbed his hand under the water. He looked considerably brighter after that, and he allowed Dean to guide him to deeper waters and begin explaining the doggy paddle.

He grinned and walked over to a dry log, resting on the sand. He had a feeling he wouldn't be getting in the water today. Instead, he pulled a paperback out of the back of the Impala—a relic he used to read all the time when spending hours on the road with Dean—and settled down to enjoy the afternoon.

He made a point not to notice the way Dean and Cas would disappear under the surface of the water for long moments, or how they came up for air only mere inches apart. And he definitely didn't notice the way they both looked like they were on cloud nine by the time they headed back to the bunker for the night. After that afternoon, Cas never complained about swimming again. In fact, he seemed to love it. Just as long as Dean was there to hold his hand.