It wasn't difficult to pick out the child among the dozen in the nursery. She was fairer than her father, and her curly hair was a deep, rich, mahogany red. That and she was gurgling away at the top of her lungs nonstop.
Yes, Donna Noble's child was quite distinctive.
The Doctor was transfixed with the baby girl, watching from the other side of the nursery window, hand pressed up against the glass. These were the times when it hurt the most. Never speaking to his best friend again, for the sake of her safety. He wanted to see her so badly, to congratulate her on her daughter's birth, to give her an enormous hug.
"So, uh... Which one's yours?"
He had to restrain himself from gasping when he turned to respond to the man who had come to stand beside him. "Well, none, actually. I'm here for a friend... Is she happy, Sean?"
Sean looked startled. "I'm sorry, do I know you?"
"You did once. I've changed since then, but I'm sure you saw me at your wedding. She didn't, of course, she never did even before, but that's for the best. Sylvia and Wilf certainly did."
After a moment shocked realization hit. "Oh my god! It's you! You can't be here, Wilfred told me what happens if she remembers you."
A melancholy smile spread over the Doctor's face. "I know, and she won't. She's just had a baby, and no matter how stubborn she thinks she is, she's not going to be running about right after that. Donna Noble, best temp in Chiswick, a mum. Now there's a sight to behold, you lucky man." He straightened his bow tie then held a hand out to Sean, clasping the opposite hand over the other man's. "Make her happy, Sean. And don't forget, every once in a while, tell her she's the most important woman in the whole of creation."
xXx
Over the years, Sean sees the Doctor many more times. They don't speak often. The Doctor is usually standing off to the side at the park with a wistful smile on his face, or they pass each other on the sidewalk, exchanging polite nods. All the kids' birthdays, he sees the man with the funny bowtie and waves. Both his birthday and Donna's birthday hold Doctor-sightings. So does their anniversary. And every time it happens, they arrive home to find a package on the front steps, signed only with love from D. Donna is always suspicious, but Sean manages to reassure her it's just one of his friends.
xXx
The last time Sean Temple sees the Doctor is the day he sits by his dying wife's bedside, holding her hand tightly in both of his, spending the hours just talking to her. Their children have all taken time off from their respective jobs to visit their sick mother. They've all gone to get something to eat, though. So he sits alone.
When he looks up, he notices the man he'd been seeing for well over half of his life. He's standing a few feet away from the bed, as if he's asking his permission to draw near.
"Are you going to let her remember now?" His voice, already worn down simply by aging, is also hoarse from the crying he's been doing when Donna is asleep.
They can both see that even though she'd been halfway between consciousness and unconsciousness, Donna is severely confused. "I feel like I know you." Her voice is subdued as well, the years ebbing away at her sass.
"You do," the Doctor whispers. "It's time, Donna. I'm going to make you remember how important you really are." He steps forward and places his hands gently on the sides of her face, closing his eyes.
Donna's eyes don't close. Instead, they turn a gorgeous golden color, smoldering, the same color as the Doctor's fingertips. It's a slow buildup to the blinding light. The tears that streak her face leave trails of gold dust in their wake and a smile breaks out. "Doctor," she whispers, the hand Sean isn't holding rising to hold onto the other man's wrist. "Oh, Doctor. Thank you. Thank you so much, you silly spaceman."
A/N: I'm giving myself feels with this one. I'm proud of myself. I think basically everyone has some form of headcanon akin to this, where the Doctor lets Donna remember just how important she is right before she passes. It's sad but it's beautiful. (The title is actually one of the titles of a Game of Thrones episode. But it works.)
