A/N: If you recognize it, I don't own it.
As much as I believe that TenII and Rose would have grown their TARDIS and continued to travel, I also believe that the Doctor deserves to rest.
Quiescence
adj. Being quiet, still, and at rest.
She sang to herself in her dreams.
He could hear her humming to herself, hear it in the very back of his mind. He was only just telepathic enough to hear it across a room, though the not-really-sound was stronger the closer he was to her. That little bit of coral, so insignificant on its own, but part of something so big and so beautiful…
Sometimes, he held it in his hands and hummed along or quietly sang the words she couldn't say. He wondered what kind of dreams she was having in her not-really sleep. Dreams of far off places and wonderful things, he would bet. Dreams of periwinkle fields and amber seas, of dusty golden sunsets and sunrises painted in shades of beauty, of a thousand planets with a thousand moons, a thousand suns, and nebulae, and fire-storms swirling up and around, whipping up dust until it became baby stars… He hoped she was dreaming of a hundred million wonderful things.
She wasn't asleep, but she was dreaming. She wasn't alive, but she was singing. She wasn't aware of anything, but she still reached out to touch his mind and soothe away his fears. He loved his someday-TARDIS dearly, but he was never going to give her true life, true wakefulness; he was never going to plant her and grow her into a real TARDIS. She was happy in her dreams and should be allowed to remain there, peacefully singing while he found his rest in a human life. They both deserved to rest.
Softly, he pushed open the pastel blue door and padded across the carpet. That little bit of coral hummed her ancient melody as he set her on his son's chest. The sleeping toddler sighed, his tiny hands automatically grasping the could-be-TARDIS.
And she sang a lullaby into his dreams.