A while ago – not a lot actually – things had been slightly different. She probably would not have found the Doctor sitting on the ground somewhere, simply enjoying the existence of the universe and everything. Also, she probably would not have laid down next to him when she was already feeling tired and thus, would have risked to place the burden on him to watch over her in case she does fall asleep.

Although they had been close friends for some time now, he also had always been a mentor figure to her, someone she had looked up to for every step he took. And in return he had been caring and comforting towards her, but now it felt as though the tables had turned. He had become vulnerable, and quite so, and she had to be the one caring. Not every step he took was still worth respecting. This change, that had come with the Doctor's regeneration, had been a difficult thing for her to take. And shortly after, until recently, she had felt like keeping her distance from him – which was not like her usual self at all. She remembered visiting him in the sick bay during the days in which he had remained unconscious and although it had given her a chance to get used to his new face, her mind had been stuck somewhere between grief and the hope that he would turn out to be the very same man still. Of course, as it was bound to happen, that hope had never been fulfilled and she had struggled a little to recognize in the man the Doctor that she had known.

By the time she had realized that he was getting on rather well with Harry now, she had tried to step into the background. Back then she had not wanted to forcefully try to get back the relationship she had with the Doctor before and would have preferred to just be forgotten by him instead. But over the course of their first adventure a new feeling of trust had begun to grow between her and his new self, and now she was not feeling as uncertain or confused anymore. Still, Sarah had a bad conscience about the ways she used to behave towards him. Within just seconds the entire thought had become so prominent in her mind that it had wiped all the tiredness from it, albeit temporarily. For quite a while she had wondered already how the Doctor and the Brigadier dealt with that kind of change, and she had wanted to ask them about it. The Brigadier, she knew, she did not really need to ask. He always kept a minimum amount of emotional distance, being quite the important military man he was, and all that. And the Doctor? Well, he was the one it happened to, so it all had to look a bit different from his perspective.

But he was still one of her closest friends and a good listener – as long as he wasn't thinking about saving the world – and if she only dared to ask, maybe he would answer. Eventually, she decided that she had to raise the topic if she wanted to settle the thought once and for all.

"I can tell you anything, can't I, Doctor?", Sarah hesitated at first, because she really wanted him not to avoid the subject like he did other times and, actually, had no idea how to begin talking about regeneration, anyway.

"Hmhm." She heard him agree without any further comment, which quite honestly didn't help her much, and she secretly wished she hadn't asked at all and gone straight to the subject instead.

A few more seconds of silence passed until Sarah had found enough words to form a sentence.

"After you regenerated, I felt I was a bit disrespectful to you, and I want to apologize for that..."

In order to check on his reaction, Sarah glanced over to him, but his gaze was fixed at the night sky.

"You? Disrespectful?", he chuckled without looking. Seemed as if he meant to put it off as a joke.

But to Sarah it wasn't a joke. She felt bad not having been at his side all the time when he might have needed a constant to guide him through his post-regeneration trauma. And all of that only because her mind had struggled to cope with the very idea. It wasn't an acceptance of her apology that she wanted to hear from him, but understanding, maybe. That's all she asked for. To find a way to understand and be understood and hoping together that she wouldn't encounter the same situation with him again.

"It's just that… I don't mean to be offensive, but I got to know you as this caring, wise gentlemen who was always on top of things." She quickly went back on some of that, because she suddenly thought she had to try much harder to make it sound not insulting. "Not that you aren't anymore, but I had so much respect for everything you did… I... I guess I saw you as a kind of father figure..." Not that Sarah really knew what a father figure was like, since she had been raised by her aunt only. But that was, in a way, what she would have expected the Doctor to tell her. That she had stuck with him because such a greater figure had been missing in her life.

But sadly, he didn't say anything. The expression on his face was blank as she dared to look, and she felt disappointed that he wasn't even going to comment on that emotional dilemma of hers.

"I'm sorry for bringing this up.", she quickly, but quietly apologized. He was not human, and maybe her feelings about it was something he simply did not understand or was not interested in. "Regeneration is probably a very commonplace thing where you come from..."

"It's not a commonplace thing.", he argued suddenly, and his voice had a strange monotone sound to it at first, "At least not for me." Sarah could see by the look in his eyes that the blankness was gone, but also that he was going through some unpleasant memories instead. "They say that the first time is always the worst, and I wasn't anywhere near Gallifrey back then, either. But I don't feel that the other two times have been much easier on me."

"Hm. You were a bit erratic when you came to.", Sarah mumbled and picked her fingernails, most likely because she felt quite uncomfortable talking, still. For a moment there she had almost forgotten that his latest self was the fourth incarnation already, and that there had been two more regenerations she had missed out on. And she wasn't entirely sure she would have wanted to be there. Then again, she could never truly leave a friend in need hanging… right?

"I still am, aren't I?", he responded to her surprise. "I don't think I've ever been this scatter-brained before; I never know what I'm doing or where I'm going… or at least I've gotten considerably worse at hiding it." Even more uncomfortable than Sarah was maybe just how the Doctor listed the things he had lost together with his last life. And he did it with such an unexpected ease... His face looked as though he wanted to let out a long, sad sigh – except he did not actually do that.

"Then suddenly, I find can't be bothered to listen to the Brigadier anymore, the idea to remain on Earth even longer troubles me, I've lost all interest in the modifications I had planned for Bessie and I used to treat my friends a little better in general, too, I think..."

Slowly, Sarah began to understand that maybe he had been in a situation not too much different from hers. He knew too well who he had been before and who he was not anymore, and she deeply wanted to say something comforting, because there were still good things about him which he had kept. The compassion, the genius, his daring ambitions to help. But suddenly she found it difficult to put together a sentence and mouth the words. Maybe because deep down she knew she couldn't disagree with him and telling him this would have just distracted from the subject at hand.

Out of the corner of her eyes, she saw him running a hand through his unruly brown curls. "In a sense, I think I've been disrespectful to myself, too. But that's just the thing, isn't it? There's no way to avoid the disappointment, not really.", he figured, then remained silent for another few seconds thinking about it.

Sarah averted her look. Maybe that's what it really was. Disappointment… But that made it sound even worse, didn't it? A part of him had actually died that day. She should have been thankful for every bit of his personality that he had kept, not hoping for him to be someone he was not anymore.

After a while, the Doctor spoke again.

"When we were on the case of the stolen disintegrator gun parts, I had that idea to put together a scanning device which should have identified and tracked our robotic culprit by the residue of its energy cells. But then, when I tried to actually build the thing, I just couldn't get it to work in time..." Judging by the tone of his voice, he sounded slightly confused to why he had not been able to.

Yes, Sarah remembered coming back from Thinktank, and finding him fiddling around with a jumbled mess of circuit boards and wires. At the time, she hadn't thought much about it, because there had been other, more pressing matters at hand, but she did remember that it had looked broken – or chaotic – from start to finish, as if it was never going to work. And if she was correct, it had pretty much fallen apart in the very first moment the Doctor had turned his back to his creation.

"...Were you very disappointed?", she wanted to know.

"Well...", he stretched the word while he assembled the rest of his answer. "A bit, I suppose. But lucky for me, I was drawn off to some new emergency straight away." Yet another pause followed, but then the Doctor came to another conclusion "In the end, I think, there's really just one way to cope with any change... One must allow oneself to get used to it and then find a way to be happy with it, too; To be optimistic about it. I have always been skeptical about my new selves at first, but then I would prefer whoever I had become to the point I almost didn't want to let go..."

For a moment or so, he smiled to himself, but then a thought crossed his mind that forced the smile to vanish again. "There is no way to live up to who I used to be, anyway..."

The young woman was a bit surprised to stare straight into his crystal blue eyes as he turned his head and eventually looked at her. "That's probably not very helpful to you, is it?", he apologized in a way, looking a bit concerned, too. Sometimes he knew the humans so well, and other times he had to ask to figure out how they worked. This appeared to be one of the latter.

The expression she returned to him probably seemed perplexed, but that was only because the realization was still dawning on her. "Actually, I think it is.", Sarah responded, because she had not expected him to feel about the matter in a similar way. And that turned out to be just the understanding she had hoped for. Slowly, a metaphorical knot seemed to unravel in her head, but she had to think some more about it until she would really be able to see what unfolded.

For now, there was something else she had to ask first.

Something very important.

"Are you happy with who you are now?"

"Yes. Yes…! I think so!" His answer came with a bit of skepticism at first, but whether he played it as a joke or actually meant it, she couldn't tell. Who knew? Maybe he couldn't tell either. But he did give her a toothy grin before he turned his head back at the night sky, suggesting he enjoyed being himself very much now.

That grin… maybe she would never quite figure out why, but the young woman found herself smiling back again, almost uncontrollably. It had happened like this just before they had set off to space station Nerva, or at least that was when she had realized it the first time. And now, she was realizing something else. His previous incarnation used to have such a gentle smile, always comforting and always reassuring. That was exactly how Sarah had felt traveling with him, even at times when she had to get him out of trouble. Now the Doctor's smile was mischievous, excited. Getting into trouble had suddenly become fun, and he didn't need to be comforting because he didn't acknowledge the seriousness of their situation in the first place. Not fully, anyway. He enjoyed playing the fool in front of his foes, didn't he?

But none of that.., she pondered in her thoughts;

...Yes, even though none of that was as clever or respect worthy as the ways his previous incarnation had gone about things, she enjoyed all of it just the same. Sometimes even more. And there, Sarah suddenly noticed that despite that period of uncertainty between them, she had never really liked him any less. She had never respected him any less. There were simply different things about him that she liked and respected now.

"Oh, I get it know!" Her sight was set towards the night sky as she exclaimed her realization and she almost laughed knowing now how silly she had been to think of herself as she had.

Suddenly, the Doctor propped himself up on his good arm."You do?", he asked with a wide eyed gaze, followed by a frown of confusion. "What do you get?"

"You're my best friend!", Sarah chuckled.

Being now within her field of view, even though she still laid back staring at the sky, Sarah noticed him furrowing his brows even more, almost looking afraid that she had dared to doubt their relationship at any point.

"But, of course I am…?"

As the young woman meant to answer, she was forced to fight down a yawn, but failed. The tiredness was creeping back into her body, but she kept talking nonetheless.

"I know. And I enjoy helping you as much as you help me. You don't have to be on top of things all the time anymore, because things are never as serious with you. They have become… more fun." If only it was that simple. What she really wanted to tell him was that he had become eccentric and silly, anti-authoritative and reckless when it came to fighting evil. None of these attributes sounded like good qualities to have, but Sarah wasn't bothered by any of them at all as she thought about it. Quite the opposite, in fact. It seemed to make him more approachable, if one could call it that. It felt like they were more on a more similar line of thought now and easier for her to close the gap between their intellects.

He could be wrong, he could make mistakes. It was okay. His friends were there to help out wherever they could.

And it might have been great to be protected and guided like his previous self used to like doing, but without it she did not feel any expectations resting on her anymore. Not that he had ever expected much from her, but before she used to feel as though she had to live up to his greatness, to learn and take in the values she had respected so much. Had she asked about it, he most likely would have helped her to get there, but now it was something else. It seemed that same genius she had wanted to learn from had left her to learn out of her own accord. And that was easier than trying to live up to some imaginary expectations. It was almost as if she was learning from a peer...

"Things usually are very serious.", the Doctor argued, following up on her words, and was still wondering about Sarah's short explanation, as far as one could guess from his expression. "But what's the point in always assuming the worst from the start?"

Under his watchful eye, Sarah turned her head to face him and smiled. There was too much she could have replied, too much to be formed into a single sentence.

He raised an eyebrow, probably confused to why she was still smiling instead of answering his, obviously rhetorical, question. "What's the matter? Did I say something funny?"

"...I am happy with who you are, too..." Sarah finally told him, resting her head back and closed her eyes for a short moment. The darkness falling over her was far too pleasant, but she managed to open them back up again. Just in time to see the Doctor grinning happily and then falling back down in the grass. It might have been just her impression, but she thought he had laid down a little closer to her now. The young woman, too, shifted until, without touching and without looking, she could clearly feel his physical presence next to her own. "I still miss your old self a bit...", she added quietly, and felt her eyes falling shut again.

"Sometimes, so do I...", admitted the Doctor, although he had lowered the level of his voice to match hers. Almost as if he meant to allow her to fall asleep. "...Maybe you'll meet him again in the future… One never knows for sure with all these time lines."

His last addition had almost gone past Sarah completely. Although her mind tried to command her body to, she could not open her eyes back up. She knew she had to get up and make her way back home. No way she wanted to be found lying in a patch of greens in the middle of London next morning – possibly by the police, too – but unfortunately for her, she simply should not have made the mistake of lying down in the first place. Now she was much too comfortable already, and knowing the Doctor close filled her with a feeling of safety, too. As often as she tried to think about getting home, her thoughts kept drifting off more and more. It just didn't seem urgent enough for her tired body to go through the trouble of lifting herself back up, making all the way to her car and driving home. Yes, way too much work when she could fall asleep right here and now… Right… here and… now...

…

…

When Sarah came to the next morning, sometime late in the noon, she had found herself lying in one of the soldier's beds at UNIT headquarters. She had slept pretty uncomfortably, being still fully clothed with leather jacket, shoes and everything. Not to mention the quality of camp beds. Naturally, her first thought had been how much she would have preferred to wake in her own bed, but that had only been the point in time when the confusion had struck her. No, she had not burned the midnight oil researching about something at UNIT, as she had hoped at first. That was not the reason she had gotten herself into this situation...

Only after minutes of a slow awakening she remembered how she had originally fallen asleep in a patch of grass in front of the National Gallery of London. Awkward, wasn't it? Thankfully, someone had brought her here so she didn't have to wake up in the middle of the city feeling like someone that got robbed and discarded afterwards. And that someone had also been both caring and careful enough not to wake her while moving her across London...

When Sarah finally assembled herself, feeling a bit ruffled after having messed up her own sleeping rhythm, she noticed a handwritten note stuck to the bedpost.

A big smile stretched across her face as she read it.

"Good day Sarah,

Harry and I have gone to Brighton to try ourselves at fishing.
You are welcome to join us after you have rested."

"- Love, the Doctor."

AUTHOR'S NOTE:

I realize it's very bold to make all of these assumptions about what the characters would say - or feel, as far as Sarah is involved as the POV character - so I'm sorry if this doesn't fit your imagination.

On a side note, I don't know exactly just how Sarah got back to UNIT. Probably has something to do with the Doctor - although with the broken shoulder he would not have been able to carry her around London. Your speculation is as good as mine!