"I think I found us a hunt."

Sam's voice wakes Dean from a fitful doze. The declaration is so full of purpose, so full of Sam, that Dean becomes instantly alert.

It's 2:56 in the morning. Sam rarely sleeps longer than 90 minutes at a stretch these days. His long slender fingers move restlessly against the blue blanket covering him, going through the muscle memory of typing on a laptop. Dean cautiously places his own hand over Sam's and squeezes softly.

"A hunt, Sam? You don't say." He carefully guards the optimism in his tone.

Sam hasn't used a laptop in three years. At 54, Sam Whittaker is the youngest resident at Sunflower Fields, a long-term care facility in Olathe, Kansas. Only a few scattered streaks of gray in his hair—still kept boyishly long—betray Sam's age. Dean, on the other hand, has gone completely gray. The past few years have been particularly rough on him.

Sam rolls his head to lock eyes with Dean. His gaze is lucid, purposeful. "Yes. Four deaths near Missoula. Looks like the work of a wendigo—possibly a chupacabra." He squeezes Dean's hand for emphasis. "Could you bring me my cell phone?"

"Sure thing, kid," Dean pats the hand and stands, his back and hips protesting tonight's choice of sleeping positions. The pamphlet that had been on his lap falls to the floor. Dealing with Early-Onset Dementia slips soundlessly under the bed and out of sight.

Dean is prepared for this farce. Lately, he's been forced to play it out nearly every night. A long-deactivated cell phone waits in a nearby drawer. Sam hasn't owned a cell phone in some time. "What do you need the phone for, Sam?"

Sam's answer, though not surprising, still sends an icy stab of grief through his heart. "I have to call my big brother," Sam insists. Even now, he hasn't lost the ability to use his patented puppy-dog gaze. "I'll need his help with this one."

Dean slips the dead phone into his brother's hand. "Thank you," Sam tells him. "You always take such good care of me." Sam never dials. He's already drifting off again, gripping the phone like a talisman. Once he's certain Sam's asleep, Dean puts the phone back in the drawer.

Like all things, Sam's symptoms started small: losing his backpack, forgetting dates and names. Soon there were mood swings, paranoia. Continuing to hunt became out of the question. He soon forgot how to drive, shower, brush his teeth, even use the toilet.

Dean, who had survived seeing his brother without a heart and without a soul found that the most challenging Sam of all was the Sam who was losing his mind. He never realized how much he depended on Sam's wits to keep him grounded, sane and alive. The doctors called it Early-Onset Familial Alzheimer's Disease. Dean called it a living hell. No, strike that. He'd been to Hell. They both had. This was worse.

He was wracked with guilt for looking forward to his brother's death—the end to their suffering. He was assured it wouldn't be long now. He'd kept up these night-time vigils in Sam's room, wanting to be there when—if—Sam needed him in the end.

Eventually, Dean nodded off, stroking his brother's hair. Some time later, he felt a warm hand on his arm.

"I think I found us a hunt."