Charlotte Pollard
From Tardis Wiki, the free Doctor Who reference
Charlotte "Charley" Pollard would've traveled with the Eighth Doctor had the Valeyard not defeated and merged with the Doctor.
A Life that Might Have Been
Charlie would've traveled with the Doctor, and later C'rizz would've joined them. (He Jests at Scars... (audio story),The Creed of the Kromon (audio story))
Behind the Scenes
It can be assumed that if the Valeyard had no interference whatsoever with her fate upon the R101, it means that her fixed point was not undone, but this is not confirmed.