Elunedd

From Tardis Wiki, the free Doctor Who reference

Elunedd was a resident at the Bryn Offa Residential Home in 2016. Due to her dementia, she regressed to her childhood and only remembered how to speak Welsh, causing communication with her family to become difficult as they only spoke English. She could still remember how to play a piece of music on the piano that she had performed at the eisteddfod in Llanilar in 1936.

Helping Jack Harkness, who was in the body of Mr Griffith, Elunedd called Gwen Cooper and mentioned Jack's name, leading her and Rhys Williams to visit Bryn Offa. She later had her mind swapped with Anwen Williams's, disturbing Mary Cooper when she found that Anwen was speaking fluent Welsh. They were all restored when Jack made a deal with the Evolved. (AUDIO: Forgotten Lives)