The Doctor sat beside the TARDIS; she was misbehaving and not wanting to leave Chiswick. Since he regenerated he had not been there. He had companions, and things, and ends of reality, and marriages. Now he was set for hiding himself, so why had his longest-term friend brought him here?
Suddenly he listened to the sound of the TARDIS and thought about running, but knew it would be useless, he was clearly there for a reason, and not knowing what day it was Earth-time made him anxious in a not very good way.
He saw himself with his arms crossed clearly not wanting to be there. Well, not that he had seen himself looking like that before, but the TARDIS and the look in the eyes and he knew.
"You won't want to come here. I didn't." the other him said punching the side of the TARDIS with a little too much force, but he didn't wince. "I'm number 13, in case you are wondering… I'm starting to…" he put his hand close to his heart and almost bended in half. "You are s-s-so stupid".
The Eleventh stood there awkward with his own body, looking at his psychic paper, waiting for River to call him for any reason at all so he could leave, the TARDIS wouldn't let Her Child in trouble, would she?
"This is a fixed point. And I'm sorry, I'm so sorry." The Thirteenth said.
Eleventh finally realized where the TARDIS had landed, not His, but his future self's. It was the Hill beside Donna's family's house. "We need to park her somewhere else, if you are dying, if I'm dying, she is going to die… Just like…"
"We told Rose, yes. This is the Place she wants to rest in peace for eternity…"
"But Donna could see…"
Too late. As the Future Doctor's legs seemed to fail him and he kneeled, Wilf screamed "DOCTOR!"
The Eleventh feared what he was about to see, but he turned and walked a little down the Hill to see Wilf trying to hold Donna who was with both her hands on her head and her mouth wide open as if she was screaming but making no sound. He turned around and looked at himself dying and wondered why the TARDIS did this.
"She is so important that every little thing about her is a fixed point. From her birth to… Aah…" he heard himself say. So he went closer to Donna instead of going back to his ship as he had intended to.
He took Donna out of Wilf's arms and she opened her eyes and whispered "Spaceman, don't you dare."
"You are dying."
"So are you. Years from now and right here." She smiled faintly, clearly with some strength just to say goodbye, or just being stubborn, she was Donna Noble after all. "Always putting on a show, huh?"
"I do my best, if you ask."
"Stupid. Bowties." she said, as he knew she would. He sometimes caught himself imagining his Earthgirl burning every bowtie in the TARDIS one day so he would stop wearing them.
"Sweetheart, don't speak…" Wilf was crying.
"She wouldn't leave without talking our ears off…" Eleventh said, then he looked over his shoulder and had one idea. He got up with Donna still in his arms.
The Future TARDIS' door was open and he walked in with Donna in his arms and laid her on the floor, Wilf helped his Thirteenth self walk back inside and when he did, every light in the TARDIS started glowing. It still looked like his TARDIS but oh so old and lived in like his Tenth self's one.
"I w-w-was going t-t-to be with y-y-you forever, forever, forever, forever…"
"You were." He said so unlike himself but wanting, no, needing to make everything he could so she would have some peace in the End.
Wilf knelled on the floor and kissed his grandchild's burning forehead, her eyes closed themselves again. Wilfred stood up and left the TARDIS and so did the Eleventh Doctor, who had decided to leave without goodbyes, but Wilf whistled and he turned to see the old earth man saluting.
The next time the Doctor saw River, he finally talked about the one companion he never talked about, and River knew that this Donna Noble was the most important woman, not only in the creation, but to the Time Lord she thought she knew so well.