Eileen Mott
From Tardis Wiki, the free Doctor Who reference
Eileen Mott was the wife of Wilfred Mott, (PROSE: Beautiful Chaos) and therefore the mother of Sylvia Noble and maternal grandmother of companion Donna Noble.
She died sometime before 2009, (PROSE: Beautiful Chaos) and the Tenth Doctor theorised that, on Christmas 2009, her corpse was converted into the Master Race, even in her grave. (TV: The End of Time)
