Don't own it, if I did, you'd all know about it.

Everyone forgets things. Sarah Jane easily admits that. She forgets things.

She forgets to lock the front door until she is halfway down the road, and has to go back to do it. She forgets the train times and ends up going down earlier or later than planned. She forgets to check the time when she is working at UNIT and is quite surprised when Harry and Sergeant Benton find her there, head on desk and fast asleep at seven o'clock the next morning.
But the one thing she could never forget was the Doctor, and the time she'd spent with him. The adventures they'd had, the people they'd met and especially the places they'd gone to - how could she ever forget that? She'd seen the birth of the Daleks, she'd attempted to bring feminism to the middle Ages, she'd seen real living dinosaurs and the Loch Ness Monster, and she'd seen the Doctor's home planet.

And speaking of the Doctor, how could she ever forget him? Not an easy person to forget. Her first Doctor, the one with the cloak, and the ruffled shirt, the fondness of Delta particles and his yellow roadster, Bessie. Her second Doctor, the one with the floppy hat, and the trailing scarf, the jelly babies and the yo-yo.
They had been forced to part by the Doctor's own people, the Time Lords. She had promised, right before facing a street that wasn't Hillview Road, in an area that wasn't South Croydon but Aberdeen, that she wouldn't forget him, and asked him not to forget her. He promised her he wouldn't.

Surely he couldn't have forgotten? She kept hoping against hope that as soon as the business on Gallifrey was fixed, he would come back for her and they could begin their life of adventure, excitement, mystery and danger all over again.

But he hasn't come.

Of course, there are things she wants to forget. She wants to forget the day when the Chinese gang she was investigating had attempted to kill her, she only just escaped with her life and some bruises. She wants to forget the day, three months ago, when Sergeant Benton was killed in front of the eyes of her, Harry, the Brig, and much of the UNIT personnel; he was shot trying to protect the rest of them.

But, funnily enough she never wants to forget the moment when she had to leave the TARDIS.

Why? It has been three months since then.

Because it is part of the life she had with the Doctor. In one universe she is Sarah Jane Smith, journalist and in the other she is Sarah Jane Smith, intergalactic traveller. She doesn't want to forget her second life.

All the memories she had with the Doctor are more special than she can say.

And because of that she doesn't want to forget.