Tearjerking videos document the decline of a gran who was gradually robbed of her memory by dementia 

Tearjerking videos document the decline of a grandmother who was gradually robbed of her memory by dementia - but never forgot the words to her favorite song.
Mary-Lou Versteegh adored the popular track ‘You Are My Sunshine’, and always sang it to her granddaughter Nicole Coenen, 24.
But in 2009, when the WWII survivor was diagnosed with Alzheimer’s and moved to a nursing home, the roles reversed.
Every time she visited, Nicole sat with Mary-Lou and crooned the words to the familiar tune, which has been covered by the likes of Ray Charles, Doris Day and Johnny Cash.