Actress Phyllida Law, mother of Oscar-winner Emma Thompson, has described the burden of caring for a parent stricken by dementia.
The Olivier Award winner, who also starred in Four Weddings and a Funeral and Harry Potter and the Deathly Hallows, looked after her mother, Meg, for several years as the degenerative disease took hold.
Speaking alongside an Alzheimer's Research UK report into the impact of dementia on carers, the 83-year-old recalled the strain that caring put her under.
She said: "The night time was particularly difficult: at dusk my mother would often think she was in the wrong house, or she would call for breakfast in the middle of the night, not knowing what time it was. When you're worn out because you haven't slept, you can be in danger of losing your temper, and that's very hard.
"I wasn't as isolated as some people, and I was lucky because I had help from the people in my mother's village and from my two daughters, who also helped me financially. But caring for ma, you couldn't leave the house without taking her with you, so you did feel very stuck a lot of the time."
The report, Dementia in the Family: the impact on carers, comes as new polling reveals that nearly a third (31%) of non-retired people aged 55 and over are worried that their family members will have to care for them in later life.
Through interviews with four families who are living with the condition, the report explores the stress and cost faced by carers, revealing how those looking after family members with dementia can become socially isolated.
Hilary Evans, chief executive of Alzheimer's Research UK, said: "For many people the festive season is a time to think about family, but for countless families across the UK dementia is taking a heavy toll, leaving people socially isolated and struggling financially.
"The experiences highlighted in this report will be recognised by people up and down the country who are dealing with the challenges of caring for a loved one with dementia."