God, the offer was a tempting one. To be once again a member of the TARDIS Crew, travelling to far off planets, stargazing in distant galaxies, battling evil monsters and insane megalomaniacs again… being with the Doctor again. Oh, yes, it was tempting. But at the same time, Sarah knew it wasn't the right choice. Sure, she'd been waiting her whole life for this opportunity, but now she was realising that life was wasted on waiting and that she had quite a few years' catching up to do.
So, with a smile on her face, she declined the Doctor's invitation.