Three days later and John hadn't heard a word from Sherlock. He hadn't shown up in school, texts went unanswered, no one answered his door, and his phone went directly to voicemail. John was starting to worry, but from the attitude of everyone at school, this was hardly unusual.
"Don't worry, John," Mike assured him on the afternoon of the fourth day as John checked his phone for the thousandth time. "Sherlock has done this before, he'll be back in a few days, maybe with some bruises, spouting some insane story about criminals and intelligence."
John nodded, but he still worried quietly. That evening as he sat at home, his phone buzzed with an alert. He leapt at it, every bone in his body praying it would be Sherlock. He read the words One new message and immediately his heart surged with hope. But when he saw it was an unrecognized number, his heart sank. Get into the car. –MH. John frowned, he didn't have a car, and he certainly knew no one with the initials MH. Except perhaps… Sherlock's mysterious older brother, his name had begun with an M. Mycroft, Mycroft Holmes. John had caught on, so when he glanced out his window and saw a black town car parked in front of his house, he threw on his worn leather jacket and sprinted to the car. The woman seated next to him gave him a nod, but refused to even look up from her phone as he peppered her with questions. Finally, John settled for silence, staring anxiously out the window of the car as London flew by. They pulled up in front of St. Bart's, and John suddenly knew exactly what was going on.
A dark form sat atop the building's ledge, staring down at the sidewalk. Somehow, John knew for a fact this figure had to be Sherlock, and before the woman next to him could say a word, he was out of the car and sprinting inside. He waved a hand at the nurse and made quickly for the stairway. For whatever reason, no one pursued him to find out why a teenage boy was running full tilt up the stairs of a hospital, and soon he was stepping out onto the roof. The sudden, cool wind caught him off guard, but once he'd steadied he ran to where he'd seen the figure sitting.
As he got closer, he saw that his suspicions had been correct. Sherlock sat on the ledge, his legs dangling over the side with his large black coat wrapped tight around him. When John called out to him, he didn't even move. The only way John knew he was alive was the loud, shaking breaths he could hear even over the breeze. John climbed on next to him, letting his legs hang over the street below. This close, he could see that Sherlock was shaking slightly. He looked peaked, his skin paler than usual, and his eyes hollow to look at. All in all, it didn't seem like he'd been eating at all since John last saw him.
"Sherlock-" John began, but realized that if Sherlock wanted to talk, he would have done so the moment John arrived. Instead of speaking more, he wrapped his arms snuggly about Sherlock's quivering form, and held on tight as Sherlock let out a low sob. Soon, Sherlock's shaking escalated to such a point that John had to slowly guide him off the ledge and onto the safety of the rooftop. Sherlock knelt like his legs couldn't hold him and John went down with him until they were pooled on the roof, and John realized Sherlock was holding onto John just as hard as he was holding onto Sherlock.
When his shaking had slowed to one every few minutes and his sobs had quieted to the occasional sniffle, John pulled back just enough to look Sherlock in the face. He pushed some the mussed curls out of the way, and kept his hand there, smoothing the hair down gently the way his mother used to when he was small and would wake from nightmares costarring the boogeyman and his own father. Now Sherlock was the one looking like a terrified child, lost and adrift. "What happened," John said quietly, careful to make it sound not like a question, but a gentle request as he rested their foreheads together.
Sherlock took a shuddering breath, and began to speak quietly, under the wind. His voice was low and his breath warm in John's ear, but his words were chilling. "My mother was diagnosed with breast cancer when I was seven. Since then she's been in and out of chemotherapy, and I've studied everything possible about chemistry and the human body. A few months ago the doctors talked to her and explained that she'd gotten worse. The tumors had spread to her lungs and they were too large to safely remove. There was nothing more they could do." John tightened his grip on Sherlock, sensing where this story was headed but silently hoping for Sherlock's sake it wasn't going where he suspected. When Sherlock's breathing hitched on a sob, however, he knew it was. "When I left you in the cab… it was because she was dying. She died a few hours ago." And the tears again wracked his body, making John cling to him and stroke his hair while he whispered useless apologies and nonsense words of comfort. He eventually folded Sherlock into his lap, holding the boy close until his tears finally dried. Sherlock curled close to John. "Take me home, John," Sherlock said in a small voice, and John knew he didn't mean the large empty house he shared with Mycroft, but John's own bedroom with the Cluedo board still spread out on the floor where they'd left it.
John nodded, and helped him up. They walked down to the nearest elevator, where Sherlock leaned against John almost entirely for support until they reached the lobby. Once there, Sherlock drew on some unknown source of strength and put up his chilly front as they left the elevator. On the other side of the lobby, between themselves and the exit, stood a young man in his mid-twenties wearing a high-quality suit and leaning upon an umbrella. When the man caught sight of Sherlock he strode up to the pair quickly.
"Thank you for taking care of my brother," he said to John, revealing himself as Mycroft, the absent sibling. "I'll take him home now." John instantly disliked this man and his condescending attitude, and especially the patronizing way he smiled down at Sherlock, as if he was a pet who had been ill and now was fixed thanks to a veterinarian.
"Actually," John said coolly, "Sherlock's going to stay with me for a bit, until he's back on his feet." Mycroft raised an eyebrow, but nodded slowly and stepped out of their way. John led Sherlock outside, where they both ignored the black town car with the woman still inside in favor of a cab John managed to summon.
They climbed into the backseat, and Sherlock stayed close to John, folding in on himself the moment the door closed between them and the real world. John held him close, and pressed a kiss to his curls. "I'm sorry, Sherlock." Sherlock made a small sound but otherwise acted as if John hadn't spoken, instead he raised his head and pressed their lips together softly. John pulled back, uncertain, but Sherlock spoke.
"John, please, I- I need to feel something. I feel so empty, John. Make it go away," Sherlock said, and John had no power to deny him any request when he looked and sounded so broken. So he lowered his lips down to meet Sherlock's, and pressed gentle healing kisses across the boy's face when their lips parted. All too soon they arrived at John's home, and only minutes later, John had Sherlock wrapped in a blanket with a cup of tea in his hand while John went downstairs to explain why a broken boy was going to be staying with them awhile to his mother.