Just Imagine...

Analysis?

"So none of you know anything about Jack?" Gwen asked in a whisper. She didn't know why she was whispering, just nervous that Jack would come back randomly she supposed.
"Other than the fact that he's gay." Owen said.
"No he's not." Gwen argued. Then she paused. "Is he?"
"Owen thinks he is," Tosh murmured, "I don't."
"And I don't care." Ianto added quickly.
"Good for you, Ianto," Sam spoke up, "and Gwen, sweetheart, you look like a deer in headlights! Relax, it wouldn't be the end of the world. Owen, stop gossiping."
"S'cuse me, Sam, I'm not your child." Owen said dryly. 
Sam looked like she was about to say something snappy, but then her phone rang in her pocket. She took it out to answer it.
"Hello?" She asked. Then she chuckled. "Speak o' the devil," she murmured to the others, "it's Hanna. Her first time using a phone."
"Aww." Gwen cooed.
"How old is she now, Sam?" Owen asked, "thirteen? Fourteen?"
Sam blinked in irritation.
"She's seven, Owen," she muttered, "I'll just step outside to take this." She added, getting up. "Hi Hanna, it's Mama..."
"So how many kids does Sam have?" Gwen inquired.
"Just the one," Owen began.
"She has two," Ianto interrupted, glaring pointedly at him, "Hanna, seven, and Alexa, five. Honestly Owen, do you pay any attention to your coworkers' lives?"
"Why should I?" Owen scoffed, "whenever Sam opens her mouth it's always 'Jay's an angel and our little girls are blessings from God and the Spirits, blah blah blah'."
"Who's Jay?" Gwen cut in.
"Sam's wusband." Ianto replied.
"Wusband?"
"Spouse."
"And Sam really balances having a young family and... this job?"
"Apparently."
"Bet it involves a lot of alcohol." Owen put in.
"Better question;" Tosh said, "since you've come here, Gwen, have you noticed any... similarities between Sam and Jack?"
"Similarities?" Gwen echoed, "what do you mean?"
"I know," Ianto said, "they've got the same personality. The same face. The same sparkle in their eyes. The same wit and charm and sense of humour and..." he trailed off when he realized everyone was staring at him. "What?" He asked.
"Have you been... studying them both, Ianto?" Owen demanded.
"No!" Ianto replied, a little too quickly, "I just noticed. Noticed things about my coworkers. Y'know, the thing you'd rather die than attempt?"
"I never said that." Owen murmured with a slight laugh.
"So what're you saying?" Gwen asked, "Jack and Sam are related?"
"Possibly," Tosh said, "I think we should ask them about it, maybe one of them knows."

But they had no idea.
After Carys had been dealt with, Owen insisted on doing DNA tests on both Sam and Jack to see if they were a match.
"Why are we doing this again?" Jack asked as Owen drew a small amount of blood from Sam, who twitched uncomfortably at the sight of her own bodily fluid. She hated looking at her own blood, so she looked away.
"Just for science purposes," Owen said unconvincingly, "just wait." He turned his back on them both and inserted the two samples into a small device. There was a moment of silence before there was a beep and a model of a DNA strand appeared on the device's little screen.
"What was that beep?" Sam asked, rolling her sleeve back down over the bandaid she'd put on.
"It means... they're a match." Owen said slowly, looking rattled.
"Wh- so that means-?" Sam said, glancing between Owen and Jack as if either of them could offer an explanation.
"The two of you are blood relatives." Owen filled in, finally looking at them again.
"I... wow," Sam murmured after a moment, laughing a little, "this is... I don't know. Jack? Whaddya think of this?"
Jack didn't say anything. He was staring at the floor with an unreadable expression.
"Jack?" Sam repeated, now looking concerned. Jack still didn't respond, just slowly walked out of the room. Sam and Owen followed him worriedly.
"Jack?" Gwen asked as he passed her by on the way out of the hub, "are you okay? Where are you going?"
Jack ignored her, that or he didn't hear her. He seemed almost like he was in some sort of trance.
"What happened?" Tosh asked Owen anxiously.
"The blood tests show that Sam and Jack's DNA are a match." Owen murmured.
"So that means...?" Ianto began, dumbfounded.
"Yeah." Owen replied without waiting for him to finish.
Gwen moved to follow Jack outside, but Sam stopped her with a hand on her shoulder.
"Umm, Gwen," she said hesitantly, "I know you're the... people-person on this team or whatever, but... can you let me take this one?"
"You sure?" Gwen asked, seeming to sense that Sam had been quite shaken by this.
"Yeah," Sam murmured, nodding, "I mean, c'mon, he's my family." She added with a nervous laugh.
She didn't buy her own words, and neither did Gwen. But nevertheless, Sam was the one to join Jack on the roof of the Millennium Centre.
"Hey there." She said casually, coming to stand next to him, though she kept herself a few feet away from him and turned her body so she was facing an opposite angle from him, even though the frigid Cardiff wind was blowing in her face.
"Hey." Jack replied quietly. It was the first time Sam had ever heard Jack sound like that. So... deflated. Almost afraid.
"You okay, buddy?" She asked gently.
Once again, Jack didn't respond. Sam sighed softly.
"If you're not gonna talk, I can just ramble to myself, y'know," she said, "been doin' it all my life. I can go on and on forever until you decide to talk to me. Let's see here, oh, we're blood relatives. That's cool, but also weird. Really weird. Why didn't we know that? There must be an explanation."
She glanced at Jack, who still wouldn't even look at her.
"Well, lemme think; there's a few possible explanations. Our families kinda drifted apart at some point, moved across the ocean from each other. We both had one common relative. Though when I think about it I don't remember there being a story in my family about anyone up and moving to Wales. What about you?"
Still no response.
"Fine. That's not it. Soo... magic. Magic? Could magic explain any of this? A family curse, perhaps? A mutation? Maybe Owen's funky little machine is messed up. We could take another test, but I think the results would be the same and we'd be right back to square one. So that leaves one more possible explanation."
Sam looked at Jack one more time, almost wishing he would stop her. But he didn't. Just stared at his feet.
"I know a bit about time travel," she began shakily, "and I'll admit that Jay and I have researched you a little bit. You've got no birth certificate, no records of parents or guardians, no siblings, aunts, uncles, grandparents, no nothin'. So technically you don't exist. But obviously you exist because you're standing right here with me. So either I'm talking to thin air and this is all a delusion or perhaps... perhaps you're not exactly who you say you are. Perhaps you're actually from the future."
She paused as Jack looked at her sharply.
"That's it, isn't it?" She pressed, feeling a worm of anxiety in her stomach though she was unsure why, "y-you're like a time traveller or something? Am I right on that?"
Jack finally spoke.
"You are." He murmured simply. Sam nodded.
"O-okay then," she stammered, smiling, "thank God you can still talk, I was gettin' worried there."
Jack dropped his gaze again but Sam could tell it was to conceal a grin this time.
"So you're from the future. How many years into the future? A hundred? Two hundred?"
"I'm from the fifty first century."
"O- ... okay, wow, that's a lot. So then that would make me your great-great-great-great-great-great-great-great-great-great-great-great-great-great-okay-running-out-of-breath-now-great-great-grandrenther? ... That's a bit of a mouthful, isn't it?"
Jack laughed quietly and Sam smiled again.
"Why not just renther?" She added.
Jack stiffened, lips sealed once again.
"Jack, c'mon," Sam murmured, taking a step closer to him, "don't try that closing up act, it's not gonna work on me."
"You mean you're okay with this?" Jack asked.
"Okay with what? You being my family?" Sam responded, "Jack, darling, how long have you known me?"
"Literally a year and a half."
"Yes, and in that time I'm sure you've learned that I'm pretty open-minded. And so is Jay. If you want us to, we will welcome you into this family with open arms and open hearts. All you have to do is let us love you."
Sam reached out to touch Jack's shoulder but he flinched away as soon as he heard the word "love".
"I don't deserve that," he muttered, "to be loved. To have a family. The family I had in the future is gone. Murdered by terrible creatures. Maybe I lost them for a reason."
"Don't say that!" Sam exclaimed, reaching for his shoulder again and gripping it tightly this time, "Jack, don't ever ever say that! It's not true! You didn't lose them for a reason! But y'know what? I think you met me for a reason. I think... something out there knew you needed me. Needed a family. And so you found me, you found all of us here." She didn't have to say that she meant the team, they both knew.
"So, what?" Jack asked with a slight laugh, "I'm your grandson now?"
"Nah, didn't ya hear what I said?" Sam replied, "I said we should shorten that thousands of generations to just one. Renther. So you'd be... my son."