The Mark II didn't remember her mother. But she knew her. She was grown from a part of her, and that part was now her heart. So she could feel the care her mother had felt, felt, would always feel—for her thief, for her daughter, for the Bad Wolf, for someone who was almost-but-not-quite-Jed, and for so many others she had/did/would love.
This love was at the Mark II's heart. She'd understood it before she'd ever understood anything else.
So when another mother came to her, desperate and pleading for help, there was only one answer she could give.
The Doctor stepped into the garden, whistling. He loved the smell of grass after a rainstorm. A beautiful day for tinkering. He headed to the Mark II.
Inside, he almost stepped into a half-eaten bowl of cereal. Tony was always leaving his things around the console. He'd have to talk to him again.
He cocked his head as he noticed the sound—something was oscillating that shouldn't be. Worriedly, he searched for the source.
It took him hours to find it—almost as if the Mark II kept moving it.
But finally he opened a panel, and—
"Oh," he said.
"Aw, can we keep them?" Rose picked up a kitten and stroked between its ears.
"What? What? No! No, of course not!"
"Please?" Tony wheedled. "They're so cute! I'll help take care of them."
The Doctor shook his head.
"Aw, come on, Doc, you can't throw them out! They're way too small," Jed said.
"They're also six! Plus the mum! We're building a timeship here, not an asylum for alley cats!" He reached for them. "Out you go."
A loud CRAZZZASH, and a blinding flash.
The Doctor sucked his slightly singed fingers. "We're keeping them," he said with a sigh.
The Mark II hummed to her new friends. She'd made a hollow for them under the console. Jed had put a pillow there, the Bad Wolf had brought them some food, and the little one with the big future had given them a fluffy giraffe that the kittens liked climbing on.
The Doctor still grumbled, but had made no further attempts to evict the little family.
The Mark II didn't think he had any right to complain. Through her mum's memories, she knew the essence of the one he was grown from.
Her mother's thief was always picking up strays.