Note: I own nothing but my own plot, everything else is the BBC's, Stephen Moffat/Mark Gatiss's, and Arthur Conan Doyle's. I just like to play here. Not beta'd or Brit-picked.

This is the fifth story in my "Heritage" series—where I take one fact, change it, and then watch as it alters every aspect of the story. In all of them, John is the grandson of an earl but is still an invalided-home army-doctor who decides to share a flat with Sherlock Holmes.

In the original mention of John's son in "Higher Heritage," John wonders, "It's weird to think my son would have been a teenager by now. Can you imagine? Listening to God knows what kind of horrific music, getting piercings or tattoos, maybe." When I wrote "Continuing Heritage" (part 4), though, I decided I wanted Ian to be younger, so I knocked a few years off. But … what if he were a teenager when he came to live with John?

### ### ###

"Is this John Brandon?"

"Yes, speaking," said John into his phone as he trotted down the pavement, wishing Sherlock's legs weren't so damned long. It was hard enough to keep up with him, but when the rain made the visibility this bad, it was almost impossible.

"You're listed as next of kin for Ian Brandon?"

And suddenly his legs weren't working at all anymore. His feet rooted themselves to the cement as his knees considered giving way altogether. "Yes, he's my son," he managed, mouth desert dry. "What happened?"

"Your son is fine, Mr Brandon," the voice at the other end said quickly, making breathing possible again. "Unfortunately, his mother, Mary Brandon … is not."

Jostled by passers-by, John worked his way over to the nearest building, sheltering under an awning and bracing a hand against the wall for support as the rain came down. "What happened?" he asked, angry with himself for how small his voice sounded, but unable to do anything about it as memories of Mary flashed through his head. The way her blond hair had glowed in the sun. The way her laugh changed when she was helplessly, hilariously tickled by something. The set look on her face when she'd told him she wanted a divorce.

"John? John!" He could hear Sherlock, but he was trying too hard to hear the voice on the phone to respond. His visions of Mary blurred suddenly into tall silhouette in front of him, followed by a concerned face bending down. "Are you all right?"

John ignored him, telling the man on the phone that he would be there as quickly as he could, and then disconnected, looking at Sherlock with … he didn't even know what was on his face.

"Harry?"

He hadn't thought he'd ever hear Sherlock's voice so gentle, but John shook his head. "Mary," he said, correcting him.

"Mary? Who's Mary?"

"My ex," said John, struggling to breathe. "I need a cab."

"What … for an ex-girlfriend? John, we've got a case…"

"Not an ex-girlfriend, Sherlock," John said, watching the road for a cab. "My ex-wife. She's just … there was an accident."

He glanced back at Sherlock just in time to see him silently mouth the word 'wife,' but all he said aloud was, "And she called you?"

John shook his head. "That was the hospital. She … she didn't make it."

"I'm sorry," Sherlock said formally, automatically, but there was more than a hint of impatience on his face. "But doesn't she have someone who could…"

"Damn it, where are the cabs?" John asked, frustrated, and then looked at his flatmate, wishing this conversation hadn't needed to come up so soon. He'd only known Sherlock a few weeks, and frankly had been looking forward to seeing how long it took for the man to deduce this. "Mary does, yes. But Ian doesn't."

"Ian?"

"Yes, Ian," John said. "My son."

Sherlock paused for only a moment before leaping toward the kerb, miraculously hailing a cab that John could have sworn hadn't been there a moment before.

#

Once the taxi was on its way, John looked over to Sherlock and said, with a conscious mimicry of their first cab ride. "You've got questions."

"A son?"

John nodded. "Yes, Ian. He's just turned fourteen. Mary wanted custody and, well, with the army, that was the best thing for him. I see him whenever I can, but … I don't know what's going to happen now."

Nor did he. They sat quietly for a moment while John tried to think of all the things he would need to do.

After a bit, he said, "I know you didn't sign up for a flatmate with a kid, much less a teenager. I'll … I'll find somewhere else. I just need a little time."

"Don't concern yourself, John. We'll think of something."

"Really?" If so many other worries hadn't been looming so large, he would have been mortified at the eagerness in his voice.

"Of course. I finally found a flatmate whose company is bearable. What's one more person?"

"A teenager," John said meaningfully.

Sherlock shrugged, but John wasn't reassured. Ian was a good kid, but he was also now a teen who'd just lost his mother. Having to move in with the father he barely knew and his eccentric, crime-solving flatmate?

One more thing to worry about.

#

"Ian?"

Sherlock heard the break in John's voice as he looked at the lanky boy alone in the waiting room. The boy huddled in a corner, staring at nothing as he absently rubbed at the blood stains on his jeans. His blond head lifted when he heard his name, and for a moment he just looked through John as if he were yet another unknown hospital employee. Then the recognition broke through, and, tears welling up in his eyes, he said, "Dad."

The two hugged then, and Sherlock noted the protective way John's arms wrapped around his son. He didn't look uncomfortable about the tears, either. Sherlock supposed John's army doctor training had accustomed him to helping people through trauma.

Sherlock, on the other hand, was decidedly uncomfortable. It wasn't that he didn't understand the sentiment, or even that he thought less of the child (teenager, he reminded himself) for the tears. Everyone reacted to trauma differently, after all, and the boy's mother had just died. He paused for a moment, trying to remember if he had cried when his father died … but no. Sherlock hadn't been close to his father, and it looked as if Ian Watson had been very close to his mother. That made a difference, he supposed.

It didn't look like the hugging was going to end any time soon, so he turned and walked to the nurse's station. He would gather information while John comforted the boy.

To each his strength, after all.

#

Later, when they left the hospital, a numb Ian walking between them, Sherlock hissed as a black car pulled up in front of them. "Mycroft," he gritted out through clenched teeth.

John, though, looked at the driver and was shaking his head. "Not this time, Sherlock. Hello, Stephens. My father sent you?"

"Yes, sir. He said you would need a ride."

John gave a weary nod and laid his hand on Ian's shoulder, guiding him to the car. "Thank him for me, would you? We'll need to go to 221B Baker Street, but … are you hungry, Ian? When's the last time you ate?"

"Dunno."

"Right," said John. "We'll need to stop for food, then. Are you coming, Sherlock?"

He realized that he was staring and, with a blink, pulled himself back to the present enough to clamber into the car behind John, who had a quirk of amusement pulling at his lips. "Your father?" Sherlock finally asked.

"He's on Ian's emergency contact list—has been ever since I joined the army, right, Ian?"

The teenager nodded, looking small. "Him and … and Mum."

"That'll be how he knew about tonight, then. I'm just surprised he's not here. Stephens, do you know why my father didn't come himself?"

"Something about a meeting that could not be postponed, sir, though I understand he made sure you were here, or he would have cancelled the meeting regardless."

"Right," said John with a sigh, as he leaned over just enough that his shoulder was pressed up against his son's. Ian leaned in and Sherlock found himself suppressing a sigh. He didn't 'do' sentiment, and even if he could allow that a child who had just lost a parent deserved a modicum of sympathy, that didn't make him any happier about having to be present for it. If John needed to comfort his grieving son, well, fine. He wasn't altogether heartless, no matter what Donovan and Anderson might think.

The fact that John had a son, though. Now, that was fascinating. It wasn't as much of a surprise to learn that he had been married, but that there was a child? How had Sherlock not known?

Oh, even he missed things sometimes, and John had only lived at Baker Street for a month. There were no (obvious) photos of a child, no "World's Best Dad" mug for his tea. There hadn't been cloying conversations on the phone of an evening. But still … he thought he had deduced everything of importance about John that first night. How could he have missed something like this?

Right now, the boy was quiet, but Sherlock knew this was numb shock—he wouldn't stay this way for long. Within a matter of days (hours?) he would rebound and start playing music and talking and generally being in the flat.

Which Sherlock had said was fine.

Sherlock didn't have much experience with teenagers—not since he'd been a teenager—but he'd been happy with that. The teenagers he'd suffered had all been rude and obnoxious, if not outright bullying. Some had been painfully shy and tried to stay out of the way of the others, but Ian didn't have that look. Judging by his hair and his clothes, he looked … popular.

What had he agreed to?

#

John knew he wasn't entirely off the hook, but he was grateful for Sherlock's restraint while they stopped for food and got Ian settled at the flat. And hadn't that been fun? At first, Ian insisted on taking the couch ("Think of your shoulder, Dad."). Then Sherlock had protested that would put a damper on his own night owl tendencies, and had offered his own bed, but that had been just too weird. Finally, John had said that for one night, either his shoulder could deal with the sofa or he and Ian could share his plenty-large-enough bed upstairs. Because, that wouldn't be awkward at all, right? Better, anyway, than Ian being entirely alone?

Now, though, they were all sitting in the living room, and John was trying to find a balance between his broken-hearted son and his (allegedly) heartless flatmate. They had talked about Mary and what they thought she would want by way of a funeral service. They had talked about what her parents were likely to decide.

John had called his former in-laws earlier to let them know Ian was safe, and to ask if there was anything he could do. He'd never been so grateful that he and Mary had managed an amicable divorce. He might not be close with the Morstans, but they had always been kind to him, in their way, and if there was something he could do to help, he wanted to.

Ian had refused all phone calls tonight, and now that they were done eating, he had withdrawn into himself and sat, staring at the telly.

"When were you going to tell me?"

He turned to Sherlock, standing in the kitchen door. "Usually you don't need to be told, Sherlock," John said with a small smile.

His flatmate shrugged. "Some things are more interesting than others."

Right, thought John. Because deducing his sister's alcohol problem was so much more interesting than the fact that John was a father. He didn't say it, though, just let his amusement show on his face. What he did say was, "I'm sorry."

"For what?"

"You wanted one flatmate, not two, and we're not really set up for a third person. It's going to be … Look, I really can look for another place to live, you know. If this is going to be a problem."

"I thought you needed a flatmate," Sherlock said, voice soft.

John gave a nod. "Well, yeah … most of my money was going toward child support and it didn't leave much extra."

Sherlock pinned him with that piercing gaze of his. "You were giving them all of it."

John sighed and gave a weary nod. "Except the army pension. I figured I'd earned that. Now, though, Ian will be living with me, so… The point is that I can afford to move out, if you want your peace and quiet."

"Don't be silly, John. I still need a flatmate," Sherlock told him. "Do you know how long it took to find one I could live with?"

He couldn't help a smile. "But that was before I brought a teenager into the flat."

"True," Sherlock said, stretching out the vowel thoughtfully. "I suppose there's just one, very important question you need to answer."

John blinked, feeling suddenly nervous. "What's that?"

"Did Mycroft know?"

#