Spoilers for the finale of the 4th season so don't read if you haven't seen Journey's End yet...
They all belong to the BBC!
She's eleven years old and the spitting image of her mother, all fiery red hair and freckled skin, and when he sees her for the first time he wants to cry. It breaks his heart a little when Donna – sweet, fantastic, brilliant Donna – looks at him as she would a stranger and grabs her little girl's hand.
'Whaddya want, then?' she asks, her voice stronger than he remembers it, harsher than he wishes he'd left it.
'She dropped this,' he says and hands the soccer ball to the little girl. 'I didn't want her running out into the street.'
Donna looks relieved and she frowns at her daughter. 'You've gotta be more careful, Jenny,' she says and his hearts constrict at the name. Some memories never really go away. She smiles up at him as though nothing has happened, which for her nothing has. 'Thanks, yeah?'
He nods, smiles through the pain. 'Don't mention it,' he says and waves good-bye before disappearing into the crowd.
She's twenty when Wilfred falls ill. He calls her to his bedside and he tells her a story about a tall man with messy hair who took her mother on adventures in a bright blue call box. She's tempted to think him batty, but his eyes are clear and focused and he's as serious as he's ever been.
'Why doesn't she talk about him, then, granddad?' she asks and he frowns, grasps her small hands in his.
'She doesn't remember, she can't remember, and for the love of your mother never, ever, mention his name in front of her.'
She nods and he falls asleep. He passes away later that night and as she watches her mother cry, her face buried into the bedspread next to his limp hand, she thinks about the time a tall man with messy hair saved her soccer ball from being flattened on the road.
She wonders if there's a way to find.
She wonders what she'd do if she did.
'You're the Doctor,' she says with a small smile and the tall man with messy hair stares at her with wide eyes. 'You're the spaceman in the big blue call box who took my mum on adventures.'
He's 906 and she's twenty-five and she's even more her mother now, the strong shoulders and piercing green eyes that dare him to lie to her when she already knows the truth. He's suddenly terrified that Donna learned the truth, that she's died and left behind her beautiful daughter.
'How do you know that?' he asks, wary.
'My granddad told me before he died.'
That saddens him. He liked Wilfred, enjoyed meeting up with the old man on occasion so he could learn of Donna's exploits while they named stars and drank coffee that smelled a little too strongly of Bushmills but that he loved anyway.
He smiles at these memories.
'Wilfred was a king among men,' he says and she nods slowly.
'Why can't mum know about you?' she asks.
He frowns, takes a deep breath. 'It would kill her if she remembered what happened. Literally kill her. And because she was so wonderful, because I loved her, I took those memories away to save her.'
Jenny nods, points to the TARDIS behind him. 'Can I see it?' she asks.
He thinks it over for all of a second – he's been traveling alone these last two years and a little company for a little while would be glorious, even if she is so young and even if she is the daughter of his former companion – before he holds his hand out to her with a gigantic grin.
'Come on, then. A quick trip and I'll have you back before supper.'
'Mum's cooking a roast. I'd prefer to miss it altogether if it's all the same to you.' She grins and grasps his hand and for a split second she's Donna.
He shakes off the deja vue and pulls her towards the call box.
'Yeah, she never was much of a cook, your mum,' he says as they walk towards the TARDIS.
The old girl practically hums when Jenny walks inside.
'And where have you been?' Donna asks as Jenny glides through the door, cheeks pink from the cold and the beautiful chants of the Ood still chiming through her head. 'I thought you'd be in for dinner.'
She smiles at her mother.
'I got caught up at the library.'
Donna smiles back. 'Not to worry. I saved a little of the roast for you.'
'Run while you still can,' her father whispers on his way up the stairs to his study and he receives a giggle from his daughter and a glare from his wife in return.
The Doctor brought her to a frozen land of wonder, a favorite of her mother's, and he introduced her to the Ood, explained who she was and what had happened to Donna, and in celebration her mother they sang for her. It was the most beautiful music she had ever heard and as she stares at her mother and thinks about the story the Doctor told her, she feels tears pool in her eyes and she rushes across the foyer to engulf the older woman in a fierce hug.
'I love you, mum,' she says, her face buried in her mother's neck.
Donna hushes her, kisses her cheek, and holds on until her daughter's quiet sobs subside.