A sad reality for more of us every year
Dementia diary: 'When your mother doesn't know who you are'
20 March 2017 Last updated at 02:39 GMT
Molly Daley was diagnosed with dementia two years ago. Her son, Joey, is making a series of videos documenting how her memory loss is affecting their lives. The series went viral after he captured one particularly heartbreaking moment.
Video journalist: Natalia Zuo
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