Sydney Wade
From Tardis Wiki, the free Doctor Who reference
Sydney Wade (born 18 July 2002[1]) played the young Melody Pond (called "the little girl" in the episodes) in the Doctor Who series 6 two-part story The Impossible Astronaut and Day of the Moon. She also voiced Melody in the Prequel (The Impossible Astronaut) webcast.
Career
She previously worked with Alex Kingston on the supernatural drama Marchlands where they played mother and daughter, immediately previous to filming their Doctor Who episodes in which they portrayed older and younger versions of the same character.[2]