Do you mean children who care for a disabled/physically or mentally ill/addicted or otherwise vulnerable family member? Just written a feature on this and it's shocking how many children are struggling alone to do the job of an adult, and a paid, professional adult, at that. The census suggests there are 175,000 children providing personal care in this country, 13,000 of primary school age and 13,000 working more than 50 hours a week.
I think very few parents sit down and think 'wouldn't it be great if my ds/dd could wipe my bum'. I think families end up in that situation because they are badly let down by health and social services. Partly because many are frightened that if schools/docors/sws find out, the children will be taken away.
Schools treat children as truants, even threatening to take parents to court instead of giving kids free transport (as is their legal duty) - they often only allow disabled children to travel on school buses for free, rather than children of disabled or ill parents, for instance. Health and social workers who support adults don't ask if that adult has dependent children. Every child in this situation is entitled to an assessment of their needs and to have those needs met but few get the help they should have. And even if they are assessed, they may then end up on a waiting list before they get any of the services that are actually the least we can provide.
VIP at the Children's Society told me children are only carers because the person they care for has unmet needs - needs that should be met by professionals.
Every local authority can cite at least one case of a child carer who has killed themselves. That's how badly we are letting these poor kids down.