*The light of the sun was fading, as his vision began to tunnel. Dean fought against burning lungs. He knew he had to keep fighting, he had to do it for Sammy.*
The sunlight glistened across the grass as Dean and Sam strode towards the lake. It was supposed to be a hot day, so the boys had decided to take a break in hunting and go for a much-needed swim. Dean ran up the dock and dove into the refreshing water. Sam followed suit and made a large splash as he cannonballed into the lake. They swam around for a bit and Dean decided to do some exploring.
He knew that this was a man-made lake and that there was a cave somewhere under the water. He figured that he may as well try to find it, as he was getting quite bored. He took a breath and dove under, eyes stinging from the water. He found what appeared to be a small cave system. Dean made a mental note of how long he had been under.
He estimated about 2 and a half minutes, and he decided he had enough time to take a quick look around. He ducked his head and shoulders into the opening and pulled out his waterproof flashlight. Dean silently thanked himself for thinking he might need it. His chest began to burn, but not enough to make him give in and surface. 'Not yet…', he thought to himself, twisting around to look further in.
It appeared to be big enough that he could fit in entirely. Dean's chest started to ache and he knew he had to surface. He had been under for much too long, and his lungs felt ready to burst. The hunter gently squeezed out of the cave and pushed off for the surface, lungs bursting as air bubbles followed him up. He surfaced gasping for air and choking out water, as Sam quickly made his way towards his brother to ask if Dean was alright.
Dean said he was fine and told Sam about the cave. The younger hunter reluctantly agreed to follow and they both took a deep breath and dove down. Sam briefly wondered how deep it was. He knew from their earlier breath-holding contests that Dean could hold his breath for over 5 minutes. That was much longer than Sam could even imagine being able to beat.
Sam could barely reach 3 minutes when he was laying perfectly still, much less swimming. In his mind, he knew he would never exceed his brother. Even still, he would always try because of the simple fact that that's what brothers do. But today was different, today he would show Dean just how far he would go to match him.
By the time the brothers reached the cave, Sam's realized his lungs were already beginning to burn. He knew he would need to surface sooner rather than later. He saw Dean disappear into a cave and Sam fought against nearly bursting lungs to follow him. Dean looked back at him, a slight smile spreading across his face, he was impressed. Sam couldn't give in now, not when his brother seemed proud. But when Dean pulled out his flashlight, Sam just couldn't take it anymore and signaled that he needed to surface.
Dean nodded and turned to begin investigating the tunnel inside the cave. Sam tried to get out of the cave, but he just didn't have enough air in his lungs and quickly became disoriented. He knew if he couldn't get Dean's attention, he would surely drown before he made it to the surface. Sam reached out to tap the older Winchester's shoulder. But just as his hand touched Dean's arm, a flurry of air bubbles rushed from Sam's nose and he tightened his grip.
Dean spun around in time to see his baby brother's lips begin to turn a horrifying shade of blue, as Sam's eyes reflected pure fear. Sam fought to hold his breath in, but the rest of his air came out in a rush and he started to breathe in. Dean quickly slammed his palm against his brother's lips and used his thumb and forefinger to pinch his nose. He raced out of the cave and up towards the surface as Sam began to buck weakly against his suffocating hold. Sam's lungs felt as though they were filled with acid.
He needed to breathe, and if he didn't soon, he thought his lungs would surely explode. As they reached the surface, Dean quickly released Sam from his grip so he could breathe. Sam began to gasp for air between bouts of choking out lake water. Dean rubbed his knuckles between his shoulders and lifted him up to rest on his chest to help him breathe easier. Once Sam caught his breath, Dean began yelling.
"What were you thinking, Sam?", He yelled. "You could have drowned!" Sam coughed weakly before softly replying, "I thought I could make it... I'm sorry." He looked at Dean with defeat in his eyes, he hadn't meant to get hurt. Sam hugged the older Winchester tightly and thanked him for saving his life.
Dean started but hugged him back. "I would never let anything happen to you Sammy," He said softly into Sam's ear. "You know I've always got your back." Dean realized that Sam had only wanted to make him happy and that he hadn't meant to push himself too far. "Tell you what," Dean said gently. "I'll go down and see if I can find an air pocket inside the cave. That way you can come with me." Sam agreed and Dean helped him swim over to the shoreline to rest.
Dean readied himself and took the deepest breath he could manage. He dove under the water and swam towards the cave, not wasting any time to get inside. Once inside he took out the flashlight and shined it towards the top of the cave. Dean saw the water glisten a bit and decided to investigate, remembering how air bubbles looked under the water. He swam up and ran his hand along the edge of the water, feeling air at the tips of his fingers.
Lifting his head out of the water, he also saw there was even a ledge someone could lean their arms on. Dean was ecstatic and immediately took a breath and left the cave, to tell Sam the good news. "Sammy!" he called, beginning to swim towards his brother. Sam looked up and made his way back over to Dean with the ghost of a smile on his lips. "There's an air pocket and a small ledge," he said cheerfully, "Come and check it out."
Sam took Dean's hand and they both dove under and swam towards the cave, Sam's grip tightening as time went on. He had a near bone-crushing grip on Dean by the time they reached the air pocket. Sam's air came out in a rush as the older Winchester lifted his head into the air pocket. He gasped for air as Dean spoke softly. "Sam," he said, "we can go down together."
Sam nodded but he looked visibly shaken. Dean had a sudden idea and he said to Sam, "We can hold hands and you just need to squeeze when you need air." Sam looked less shaken and agreed. They both drew a sharp breath and dove under the water, Dean pulling out his flashlight so they could see. He shined it towards the back of the cave and a long tunnel came into view.
The brothers swam towards it and Sam tightened his grip on Dean's hand tremendously. Dean turned to Sam with a questioning look and saw the fear in the younger Winchester's eyes. Sam was terrified, and he knew it was to be expected as Sam had nearly drowned as a young child. He had fallen through a patch of ice as John took them on their first family hunt. Dean had dove into the water to rescue him after Sam had gotten turned around and trapped under the ice.
Dean flashed his brother an understanding look, and they continued along the tunnel. Once inside, he felt Sam's body shudder and turned to see what was wrong. Sam's lips were pursed and his chest began to spasm. 'Oh shit,' Dean thought. 'He's having contractions' Sam winced as more contractions hit and he squeezed Dean's hand tightly.
Some air escaped from Sam's lips and Dean nodded, kicking strongly around and back out of the tunnel. His grip turned to iron around the older hunter's hand, and he began to swim faster. Once they reached the surface, they both gasped for air. Dean had been nearing his limit as well. He looked over at his little brother, keeping a close eye on him until he caught his breath.