A Granada Reports investigation has found elderly people, in their 80s, who have little choice but to provide round-the-clock care for disabled loved ones for free.
It is free because carers lose their carer's allowance when they reach pension age. The charity Age UK estimates that saves the Government £15bn each year.
Yet that free care can come at a cost to the elderly carer's own health. Our political correspondent Dan Hewitt has this special report