Eileen Mott
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Eileen Mott was the wife of Wilfred Mott, (PROSE: Beautiful Chaos) and therefore the mother of Sylvia Mott and maternal grandmother of companion Donna Noble.
When Donna believed that she was in 1960s London, she stated that Eileen and Wilf's relationship would be in their early days. (AUDIO: The Creeping Death)
She died sometime before 2009. (PROSE: Beautiful Chaos) Wilfred was later worried that his wife might have been turned into one of the Master Race inside her grave. (TV: The End of Time)