It's all AU.

It wasn't until Jack coughed back into life that the Doctor realised that he'd never seen it happen before. He'd heard about it, here, but this was the first time he'd seen it, and it shook him to the core. The extreme wrongness of it. The way it went so completely against nature - not life rushing out of a body the way it should, but into it. He was shaking as he resisted the urge to run, run away from this abhorrence of nature and bent to gather the newly-woken, confused and terrified Jack into his arms.

It took a while of just holding Jack - sitting on the floor and leaning back against the bed with Jack practically in his lap, rocking him like a child - to calm him into coherence. But eventually calm came, and Jack was able to tell the Doctor what had happened. There then followed a period of self-recrimination from the Doctor which Jack promptly put an end to by straddling him and kissing the hell out of him.

No way the Doctor could continue to think with Jack kissing him like that.