Pete Tyler

J was quiet.

Which immediately put River on edge.

J was NEVER silent. Not ever. No matter how much she begged or pleaded for just a single hour of peace and quiet, he could barely make it 5 minutes without talking about something. Not even covering his mouth with tape seemed to work at keeping the noise low, he'd just keep talking past it, somehow, it must be a Time Lord thing.

Whatever it was, River did not like it one bit.

It would be one thing if he was quiet because he was thoughtful, with that little smile on his face when he was thinking about something. Or if he was quiet because he was in such awe of something that it robbed him of his words for a minute or two.

It was another thing when he was grim and quiet and looking at the console of his TARDIS, having piloted them somewhere as smoothly as ever, and was just…staring at the monitor.

"Alright," she huffed, moving over to his side and resting her hip against the console, crossing her arms, "Are you going to tell me what the frowny face is about or am I going to have to pry it out of you? And," she cut in when he opened his mouth to reply, "Don't forget, J, I'm your best mate, I know all your tickle spots."

She nearly snorted when he took a step back and put his hand on the side of his ribs to cover it protectively.

"What's going on?" she asked.

J sighed, and turned to the console, moving the monitor so she could see what he was looking at.

Her eyes widened, seeing a very familiar person walking down the street with another familiar individual beside him, "Is that…"

J nodded, "Dad, his 9th incarnation, with Rose Tyler."

"Alright," River said slowly, looking at him cautiously and weighing what she wanted to say next, "Why are we here?" seemed like a safe question.

She knew how he felt about that particular companion of his father's. She knew how he felt about the next incarnation of his father, too. He blamed the 10th Doctor far more than the 9th for the time it took his parents to finally fully Link. Because 9 had been the one to travel with Rose, not start to fall in love with her. SHE thought that 9 probably had started the process and 10 had just gotten hit with the full brunt of it, being better able to express himself and more healed from the War, but J wouldn't hear of it. In his opinion, 9 would have kept going with Rose as just a companion whereas 10 had been the one on the cusp of making her more. Sure, yes, 10 was more healed and maybe that gave the boost to opening up to Rose more, but 9 had not been the one to act like a puppy around her.

And 10 had been the one that Evy had found, 10 had been the one that travelled with her and didn't Link to her.

And no matter how many times Evy told him it was HER choice not to remove her Perception Filter to allow the Linking, J still chose to blame the Doctor, HE hadn't been ready for the Linking, HE hadn't been in a good place to have it be as meaningful an experience as it ought to have been, HE had been the one hung up on Rose when Evy found him.

So for him to choose an adventure where they were likely to run into Rose…she couldn't fathom WHY he'd pick it. Because he had manually put in the coordinates, this wasn't a mystery tour. Even if it HAD been, she doubted his TARDIS would take him anywhere he'd interact with someone that affected him as negatively as Rose would.

J let out a long breath, rubbing the side of his face in the way his father's 10th self often did, "It's November the 7th, 1987," he began, "The day the world almost ended. Because someone tried to rewrite time."

River snorted, "Time CAN be rewritten," she remarked, "I've seen you and your parents do it loads of times."

"Yeah, because we actually know what we're doing," he countered, an edge of bitterness and anger in his voice, as though he'd seen someone try to do the same, not knowing what they were doing, and mucked it up so much worse, "And that's why we're here. Riv…if you're going to travel with me, if we're really going to do this, travel all around, be Spaceman and Timegirl…I…" he took a breath, "I need to know that you'll make the right choices."

She gave him an unamused look, "You once blew up the chemistry labs of the university because you were bored and wanted to know what color it would be if you mixed every chemical they had together…and you want to talk to ME about making good choices?"

"I'm not talking about little things," J huffed, ignoring her snort at how blowing up part of the university had been a 'little thing' to him, "I'm talking about time, events and points in time and knowing whether they CAN be changed or should not be. If I'm not there, Riv, I need to know you'll know the difference," he glanced back at the monitor, "It's why we're here."

"What, so I can go through a test course of different points in time?" she scoffed, "I KNOW the difference between fixed points and still points and everything in between, J."

"I know," he swallowed hard, "I know you know the difference Riv, but we graduate in a week," he reminded her, of their plans to go out and see the universe together once they were out of school, "Knowing the difference between them is NOT the same as experiencing them. Some can be…" he let out a breath, "Tempting," he warned, "There are going to be events, major ones, ones that'll affect whole worlds or even OUR worlds, that will come up, and believe me, you'll want to change them…you'll want to SO bad," his voice cracked a bit, causing her to frown, as he cleared his throat and continued, "But you can't," he emphasized, "No matter what, you can't. And that's why we're here," he repeated.

"What's out those doors?" River asked, getting something of an odd feeling that this wasn't just a trip for HER but him as well.

"What happens when you give in to temptation."

~8~

It was strange, River thought, just how contradictory the Doctor could be. In the middle of danger he was either the most brilliant man ever, who knew what to say and do to get everyone out alive and could work out any problem that came his way…or he was a chicken running around with its head cut off and missing the obvious.

(She could write a paper about whether there was a reason for it or if the direction the wind was blowing affected it.)

Right now it was the latter.

Because she and J were sitting in a church, in a pew, literally within eyesight of him, completely obvious…and the man was barely noticing them. Of course they had on low level perception filters, but set so low that it would really only keep the Doctor from sensing he wasn't the only Time Lord there. Even then he hadn't taken notice of pretty much anyone else there besides Rose, her family, and the couple who had been about to get married before the world went to hell.

She…hadn't ever given much thought to what would happen if a fixed point, or an established point, in time was altered. She had just assumed, arrogantly so, that she would abide by the laws of time, change what she could, and not attempt to alter those she couldn't. She had escaped Kovarian, she had technically already 'killed' the Doctor, she was free. She had just planned not to cause any events or get caught in any events that involved fixed points or where she or those she cared about were in danger.

…seeing what had happened to cause all this…she had a much different outlook.

She and J had been walking down the road, on the other side of the street from where he'd said Rose's father was about to be hit by a car. She'd been horrified, not just by the fact that they were about to witness a fatal accident, but the matter-of-fact way he'd said it. Until he explained that Rose's father died when she was a baby, running late from picking up a gift for a wedding, didn't see the car, and ended up dying alone on the pavement, gone before the ambulance could get there.

He'd just nodded over to where it was about to happen, and told her to watch.

J would NEVER be so callous about someone dying, so she knew there was more going on. She'd turned to watch as, right when the car turned the corner, Rose ran from an alley and shoved her father out of the way.

She could only stare.

It took her a longer minute than she would admit to process what happened and what it meant, not just for the world, for time, but for herself as well.

She had never considered a world where J could be injured or die permanently, the way Pete Tyler was. She always imagined, if anything like that was going to happen, she'd be right there and jump in the way. But it was foolish to expect that.

She had never really given thought to J or the Doctor or Evy or her parents being in that much danger, that hurt, because they were always so awe-inspiring and clever, it just didn't seem possible for them to end up in a situation like that.

Seeing Rose's father, seeing Rose running to stop it, being told there was already a version of Rose there who hadn't been able to muster the courage to just sit with her father as he died the first time…it hit her all the harder now.

What would she do if she was in a situation like that? If it was J or someone else she cared?

When she saw Rose save her father, a part of her said 'that.'

She would do exactly the same, risk anything, to save the ones she cared about.

Because…nothing happened, nothing changed, the skies didn't open up and the earth didn't tear itself apart. Pete just got up and walked off with Rose and the 9th Doctor, life went on.

It wasn't till J said they should head to the church where the wedding was being held that she began to get a pit in her stomach, because he sounded regretful, like he didn't want to go either, but like they HAD to.

It seemed like they were just in time to witness all hell break loose as black, winged aliens seemed to appear out of nowhere and swoop down, disappearing people. There was panic at the wedding party, of course, given there was an attack going on during their special day and no one knew what was happening. The Doctor had run up to Rose and Peter, who had just arrived, and ushered everyone into the church, her and J included, and it was just chaos after.

The aliens, Reapers, that was what J had called them, were slamming themselves at the doors, trying to get in, no one was answering any phones or calls for help, people were vanishing everywhere.

And that was how she learned what happened when an established event was altered to the point that the Blinovitch Limitation Effect was caused. It could draw out Reapers, aliens who sought out disturbances in time, like paradoxes, and acted as bacteria, taking advantage of the wound in time by eating literally everything in the area and spreading out from it. Because of Rose's actions, because there were two sets of her there already, the Reapers had appeared and they could not be destroyed or stopped. They could only be slowed for a time, like hiding in a Church, older buildings were stronger buildings. Nothing in the universe could harm them and only repairing the tear in time would banish them away.

Meaning Pete Tyler would have to die, as had been established in Rose's personal history.

Oh there WERE times where it could change, history could be altered.

But she understood now what J was trying to say about knowing WHEN it could be, about being distant and clinical and detached when it was personal.

If the Doctor had not known who Pete was, if he had just been a random man he'd saved, that could be one thing, if circumstances were right. But he was Rose's father, the Doctor's companion, he KNEW her history which made the event more permanent. The fact that there were two sets of them there had already made time vulnerable and weak, any little change could have set off the Reapers because of it. The first go around, maybe the Reapers would be held back, but NOT the second. Because the TARDIS had set down once, become a part of events, which meant to set down again…those same events HAD to happen and they didn't.

J had been solemn as he told her that this wouldn't have been as big a problem ages ago, when Gallifrey was still around, the Time Lords were adept at preventing Reapers from appearing, repairing time themselves, but with them effectively gone, there was only the Doctor left to fix things.

It was a heavy thing to hear, to witness, to see and know what would happen if the wrong choice was made. Reapers would destroy everything and spread out from the origin of the wound to devour whatever was in their way, reality basically being eaten alive and every man, woman, and child falling victim to being erased.

Would that change her mind? she wondered. To know that, if she saved J from a similar fate, it would mean the death and destruction of everyone else in the Universe?

He'd hate her for it, she knew, if she even tried. He'd genuinely never forgive her if she put his life above the universe.

Could she live with that? Could she live with either his hatred or all that death hanging over her?

She didn't have time to consider it, because someone screamed, and she looked up to see Rose holding a baby in her arms, a Reaper materializing in the room, and the Doctor trying to draw its attention to him to keep everyone else safe.

And, just like that, in the blink of an eye, the Reaper swooped down…and the Doctor was gone.

~8~

Seeing the Doctor step out of the church was the first time River took a deep breath since the Reapers appeared. She reached out to link her arm with J's, the man had been so serious and grim and tense this entire trip but the last leg of it had really put him through the wringer. Never before had they ever been this much like Time Lords were supposed to be, sentinels who watched and didn't interfere. And she knew it killed him to have to be that way. To sit there and watch the chaos, the panic, the sacrifice, and not make a move to help, to even offer reassurance or words of comfort. J was far too much like his parents, caring about everyone.

When the Doctor disappeared and the humans panicked, he had to be silent, to sit there as Pete Tyler offered to end his own life to set the world to rights. As much as he hated Rose, not even he would have stood aside and watched her break down, in any other circumstance than this, where the perception filters required them to not draw attention to themselves.

Things were well again, though.

…or as well as they could be while they stood on the steps of the church, watching as Rose sobbed over the body of her father, lying in the middle of the road, dead, the Doctor standing nearby as she grieved.

"Come on," J spoke, his voice thick as he turned to lead her away, back to his TARDIS, not saying another word till he reached the console and set them to the Vortex. Once they were away, he turned to her, crossing his arms and leaning against the console, "Do you understand now?" he asked her, trying for serious and stern, but only managing it for a moment before he was slumping, seeming more defeated, "Please tell me you understand," he dragged a hand down his face, "I don't think I can handle doing this again."

River mimicked him, leaning against a support beam, her arms crossed, "I do," she told him, this time being serious too, "There are going to be hard choices," she said, what she'd learned from this, "Temptations, times where I want to say 'to hell with it' and throw the rules away…and I can't, I shouldn't, because some rules, not all of them but some, were put in place for a reason, to keep even worse things happening."

J nodded, "Exactly," he said, though there was an odd tone to his voice, as though he hated to say it, like he'd experienced more than his fair share of the same, "There will be times you'd give anything to change what happens…" he looked down, grief heavy on his face, "And you have to remember that you can't," he looked up at her.

She frowned at the look in his eyes, one that felt as though he were seeing a ghost at the same time as being utterly haunted and…not for the first time…she wondered what he had seen as a child, what events his parents had told him of as he grew, that now, as an adult, running into them every so often, he knew what was coming and couldn't change it, because it had already been established events…and from time travelers.

"J…" she began.

He shook his head, "There are some places, some times, where you can bend the rules, stretch them, where things snap back, or even when changing time IS part of events," he waved it off, the topic getting away from him, "Point is, it can only be done very, very carefully, and you really have to KNOW when that can happen otherwise…" he gestured at the doors as though to say 'that's what happens.'

"And," River continued for him, "Chances are, the person you're trying to save or alter time for won't thank you for doing it, if it means everything else dies because of them. I certainly wouldn't."

J looked at her a long while, the corner of his lip quirking up the smallest amount, "No," he agreed, sounding more like he'd been given some sort of reassurance he hadn't known he needed, "You wouldn't."

"I'd kick your arse if you even tried," she warned him, smirking.

"Oh, I know, and those heels!" he grimaced and, just like that, it was like he was back to his old, hyper, excitable self, "Well, now that the boring, serious stuff is out of the way…mystery tour?" he grinned, waggling his eyebrows at the temptation of a tour.

River chuckled, clad to see him back to sorts again and waved him on. She could do with some running for her life after sitting in a church and watching the world fall apart then piece itself back together again.

A nice distraction was what she needed.

…to lull J into a false sense of security and let him THINK she was letting his odd behavior go, if only so she could pounce later and get answers from him when he least expected it.

A/N: I felt so bad for J having to do this :( But I felt like there was a really important lesson that River would need to learn before she really started her journey as a Time Traveler :( What can change, what can't, and what happens if you try to change what shouldn't be changed :( Because River isn't quite like him, she may not have that sense about her and so she has to be so much more careful about the things she changes.

I feel like he knows there will be times River messes up, Lake Silencio coming to mind, but that, as long as you have a PLAN for how to fix it (like his parents do), then it can be ok to alter time. Or that, sometimes, it's already an established event to alter time (like how Silencio occurred for his parents as he was being born, so technically an established event in his personal history), but that it must always snap back to normal.

I think it was something J needed as well on multiple levels.

He needed a reminder for himself that, as much as he may hate the losses he knows are coming...he has to LET it happen, or risk this happening :(

He needed that reassurance from River that she wouldn't blame him, that she'd want him to let her go if it meant keeping the universe safe :(

And...so that River would know that he tried, that he WANTED to change those moments that are coming, but he literally can't, because of consequences like this :( He wanted to her to know he doesn't make those choices lightly, and he hates them, and he's not choosing to just 'let' her die one day, but that he has no choice :'(

Such a heavy burden :(