It began with a cough.
The Doctor didn't think it was anything important; it was merely part of his Time Lord and human parts meshing. Rose was happy to let it go, because he was her Doctor and, really, a little illness was the last thing she wanted to worry about.
But then it got worse.
"You have to get him to a doctor," Jackie said, feeling the Doctor's forehead. "He's burning up."
"What can a doctor do for him, Mum? He's an alien."
"You heard what the… other one said – he's human. He needs a doctor."
"I am a doctor," he said in between coughs. "And I'm fine."
Jackie shook her head. "If that ain't proof for you, Rose, I don't know what is."
"What?"
"He's never been 'fine'."
"I'm afraid the biopsy results show that you have lung cancer, Mr Smith," the young female doctor said.
"But… there's something you can do, right?" Rose asked, one hand in the Doctor's and one resting on his hospital bed. "I mean, this is the Golden Age, right? You must have something you can do?"
She shook her head. "I'm sorry. The cancer has spread too far and is too virulent. We could operate, but it would increase his life-span by a week at best."
Rose shook her head. "No. No. I… this can't…"
The Doctor squeezed her hand. "It's alright, Rose. I've lived a long life – or at least, I remember living a long one." He smiled that goofy smile, and she shook her head.
"Do you know how long I waited for the chance to get back to you? And then… then I just got sent away, and I thought… I thought… But then you were there, and you were you. My Doctor. And you said… you said…"
"I love you, Rose Tyler."
She slipped her hand out of his and looked away, unable to bear it.
"Mr Smith, we estimate that you have about a week to live." The young lady swallowed. "We have facilitators who will be able to help you get your accounts in order."
"Thank you, Dr Jones," the Doctor said, subtly motioning her away. She pulled the privacy curtain around the patient and his girlfriend and then left.
"Maybe he lied. Maybe the other you lied. I mean, maybe he was wrong. You've been wrong before. Maybe you can regenerate."
He shook his head ruefully. "Rose, this is my time-travelling catching up to me. Time Lords take all that wibbly-wobbly timey-wimey energy in their stride – even humans can adapt – but me, I'm a special case. Last of the human regenerations. An impossibility. The one thing in the universe that doesn't quite make sense."
Rose snorted through her tears. "Full of yourself, aren't you?"
"Oh yes. But see, the universe doesn't like impossible things lying about. Tries its best to get rid of them, in fact. So now it's time to be getting rid of me."
"No. I'm not letting you die, Doctor. Not this time."
The Doctor's omnipresent smile faltered as he said, "Yes. You are."
Jackie hugged her daughter close as they read the inscription for the hundredth time.
Here Lies A Doctor
It was simple, but Rose was glad that her mother had chosen it when she was unable to do anything but cry. It fitted; it was what he would have wanted.
"Here lies a doctor," she whispered, unable to stop her thoughts from turning to the other Doctor. He had given up his own happiness in hope of hers. But now all she had were three little words, spoken from a different man's lips.
"I love you." She smiled; it was all she'd ever wanted, in the end.