Adjustments
A gun on the hat-rack. Another set of hands on the console. Another mind in the TARDIS, always open, always questing.
Some things take getting used to. He'd gotten used to being alone in his head these past few years. There are only a handful of people in the universe who he can link with these days, and he hasn't seen any of them recently. Jenny's presence is like stepping into the warmth when you're freezing; so good that it hurts. Her mind is so open. He has to readjust to the connection, the constant feeling in his mind.
He has to get used to things being out of place, because Jenny has a bad habit of picking something up and forgetting to put it back where it belongs. He found King Arthur stuck in with his books on gaseous chemo-biology. A week ago there was a spanner left in the kitchen next to an open box of cookies, and two days ago he noticed a glass of water sitting in the exercise room. If he's lucky she'll grow out of that soon.
The Doctor is remembering how to cook, day by day. How long has it been since he really tried to do this? The TARDIS usually turned something up when he or whoever he had along was hungry. It didn't matter much. But Jenny's never had tea. Never had scones or brownies or chips. Never had pancakes, bacon and eggs like they cook in America, or De'tal from a proper Barcelona recipe. Never had French toast. And that's definitely a tragedy. So the Doctor cooks for her.
He has to get used to feet pounding down the hall, the occasional crash of something down the corridors. Jenny's a bit of a klutz. Not when she's fighting. In danger she moves like white lightning, smooth and graceful. But when she's calm, there's so much going on in her head that she forgets to watch her feet.
The Doctor tries his best to find things she can help with around the ship. She wants to be useful, show what she can do. She's such a kid, so eager to please and prove herself. He shows her some of the simple repairs, lets her help with fused circuits and add mercury to the fluid links. If she'd pick her boots up and put them away, that'd be nice too. Or her clothes.
He has to get used to questions. When he traveled with humans, he gave them what they had to know and got on with life. He loved them all, but they wouldn't understand if he tried to explain properly. Jenny is different. She's so far behind in her learning that it's like they're going through nursery school, but she soaks up everything he teaches her, and her mind begs for more. Temporal calculations, mechanics, piloting, even the Shadow Proclamation, which she memorized and then debated with him. There's always a question on her lips. It's been centuries since the last time he really tried to teach someone. He hopes he's getting it right.
He has to get used to having a teenager on board. Jenny may look like she's around two hundred, but he places her emotional status at eighty, tops. Jenny is definitely a teenager, all her emotions intense; powerful emotions he can feel from the other end of the TARDIS. She pours off interest and happiness and curiosity like a star giving off heat. She hasn't learned to control her mind yet. When she's happy it's like there's a small sun shining. When she's frustrated he puts up shields just to keep out the mental noise.
And her impulsiveness. That still catches him off guard. He thought humans missed the point of 'DON'T wander off?' Hah. They didn't hold a candle to Jenny. She throws herself into danger with a fierceness that's almost joy. It scares thirty years out of him sometimes. He's going to choose a few very safe planets for a while. He had to get used to the fact that she loves danger. He might face it, grin at it and kick it in the shins, but Jenny revels in it. She loves to test her body as much as her mind. So he tried taking her running, Kardal riding, swimming, rock-climbing. She loved every minute of it.
He has to get used to her face, her voice. It took a week to get used to her calling 'Father!' Sometimes that voice opens wounds in his soul. She looks so much like another little girl. So much like a lovely young woman who had spread her arms out in red grass and laughed. He has to get used to that, cover up the gash. She isn't that girl.
Late at night, he has to get used to the fear he feels. Her timelines are full of possible deaths. At times he feels like confining her to the TARDIS until she's five hundred, just to keep her out of harm's way. He hasn't felt like that about anyone since…
Some things are new. But the Doctor is adjusting.