Joanna Horton

 voiced the first incarnation of Brooke for several stories in The Diary of River Song: Series Three. Horton's physical resemblance to Sydney Wade if Wade had been an adult was noted on Rec.arts.drwho and Gallifrey Base.

The Diary of River Song
As Brooke
 * The Lady in the Lake
 * A Requiem for the Doctor
 * My Dinner with Andrew