According to research, around three in every five people with dementia will go missing at least once during the course of their illness.
It can be a very frightening experience for them but also their family.
Now a new scheme, the first of it's kind in the world, is being piloted in the Thames Valley to help find people with memory problems who go missing.
Mel Bloor talks to dementia patient Ralph Burridge and his wife Jan, George Holland - the great nephew of missing Sussex pensioner Nellie Herriott, Dr Rupert McShane from Oxford Health NHS Foundation Trust who came up with the idea, volunteer Naomi Manuel and Service Manager Deborah Ginns.
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Lemurs and Emperor Tamarins at Cotswold Wildlife Park have been joining in the festive spirit.
Lucy has the Christmas Eve forecast for the east of the Meridian region.
Lucy has the Christmas Eve weather for the west of the Meridian region.