He still had the nightmares. Every. Single. Night. He dreamed of Afghanistan, and he wished it would stop. Sherlock had taken notice as well, and would wake John when it got too bad. He didn't only dream of Afghanistan, though. Ever since Mary had died, she appeared in his dreams as well.
Most nights, the dreams were the same.
Mary would be screaming, and gripping John's hand. He would tell her, "It's okay. It's going to be alright."
Gunshots would go off, and the setting would change from a hospital room to the battlefield. John would be in his uniform, gun in hand, and the enemy would be surrounding him. They would fire at him, and he would fire back. Mary would scream, and shout, and cry behind him, and he couldn't help but wish that he didn't have to defend her. He wished he could just stay at her side until their daughter would enter the world, blinking into the Afghan sun.
Well, a hospital room was more preferable.
But this was the way it had to be. He had to protect his wife, and his soon to be born daughter. He couldn't wait to finally see her face, and he couldn't wait for he and Mary to be able to hold her for the first time.
After all of the surrounding enemies were dead, or had fled, he would turn to his wife, who seemed to be giving up.
"Mary," He would day, running to her side. "Come on, don't give up."
She would cry. "I can't do it, John."
"You can, Mary," His eyes would tear up at his wife's tear streaked face.
Her pain was audible in her sobs. "It hurts so badly."
"I know." John moved to the lower half of her body, and he would lift Mary's hospital gown. He smiled. "You're almost there! Mary, come on!" Mary's face wrenched, and she let out a loud scream as she pushed forward.
After what would seem like hours, John would finally hold the crying baby girl in his hands. He would smile down at his daughter, who was still covered in blood from the birth. He immediately takes her to Mary, who weakly reaches out her hand to her child. He would give her a bright smile, and hand the girl to her. Mary holds the baby close to her chest, and presses her lips to the infant's forehead.
"Katherine," Mary looks to John, giving him a smile. "Katherine Marie."
He would nod. "Katherine Marie Watson."
Mary suddenly falls back against the wall of the building she had lay in front of. John quickly got on his knees next to her and grabbed Katherine.
"Mary?" His voice was frantic.
As he tried to desperately get a response from his wife, who's temperature was cooling dramatically, Katherine went limp in his arms, and her breathing would stop.
After losing both his wife and his daughter, John had moved back into 221b Baker Street with Sherlock. He did his best to keep busy with cases, but Sherlock started doing some cases alone. He would leave the flat at night, and he wouldn't let John go with him.
"It's a case," Sherlock would say. "Nothing more. Nothing less. Go back to sleep, you need it terribly."
After weeks of the detective sneaking out, and changes in his behaviour, John got a phone call from one of Sherlock's homeless network members, whom Sherlock had bought a cheap mobile for easy contact.
"Hello?" John said into his phone.
"John?" Said a voice. "It's Wiggins. Bill Wiggins. There's a problem."
"What?" John asked. "What's happened?"
"It's Shezza," Bill said. "Sherlock, sorry. He's back at the den."
"He's back at the– Jesus." John stood from the sofa and ran to the door of the flat, grabbing his coat as he went. "Same as before?"
"Yeah," Bill seemed distracted. "He ain't lookin' too well. Should probably come get him, take him to your flat. He need some tendin' to."
"I'm on my way." John hung up.
After getting Sherlock, and taking him back to the flat, John knew he couldn't deal with him alone. He called Molly, who showed up quickly. She had taken a urine sample from Sherlock, and went back to Bart's. By the time she came back with the results, she told John that he had been using, although it was fairly obvious.
Sherlock had gone unconscious by then. He wasn't responding to John or Molly. John called an ambulance, which showed up within several minutes and they took him to hospital.
Sherlock had died a week later. Overdose.
And John blamed himself for not helping him, and not noticing his substance abuse earlier.
Four years later, John was still waiting for Sherlock to return.
"John," Molly said after they went to get coffee one day. "I did the autopsy myself. I hate that he overdosed, and I hate that none of us could have helped him, but you need to accept that he is dead. He truly is." She was crying.
"You did the autopsy last time too," John said. "He faked his death then, so why not now?"
After four years, three months, and twenty six days, John couldn't take it anymore. He knew Sherlock wasn't coming back. He took his gun from its drawer and placed it to his temple. Tears slid down his cheeks. He wasn't even going to leave a note. He was just going to do it.
So he pulled the trigger.
John had never believed in an afterlife. He always believed that death would be a never ending darkness that would drive you insane if you were somehow conscious.
He was wrong.
The first thing he saw after death was the engraving on black marble, which read "Sherlock Holmes".
He moved his eyes up, to see the man himself sat upon his own tombstone. He had his right leg crossed atop his left and his violin was at his chin. He slid his bow across the strings as he played a song, which John immediately recognized as a waltz.
His and Mary's Waltz.
He turned his head to his right, where Mary Watson sat upon her own grave marker. An infant lay in her arms and she smiled at John. John held out his arms as the waltz continued to play, and Mary handed him the baby.
He smiled down at his daughter. "Katherine Marie Watson."
Mary smiled. "Katherine Marie Watson."
Mary scooted from her tombstone across the small space between her's and John's markers. She sat next to him, and he handed her the baby again. He wrapped an arm around her waist as she cradled the baby. Mary looked up at him, and he leaned down and pressed a warm kiss to her lips. When their lips parted, he turned to Sherlock as the waltz he played ended.
Sherlock looked at the Watsons. "After four years."
Mary leaned her head against John's shoulder, and John smiled at Sherlock. His best friend smiled and John smiled back.
"Finally." John said. "We are together at last."
Mary looked down at her daughter, then at her husband and Sherlock. "All four of us."