By Katherine Sellgren
BBC News education reporter
The 2001 census revealed 175,000 young carers in the UK
Children with caring responsibilities are often "unidentified, unsupported and without a voice", research by the watchdog Ofsted has found.
Inspectors said not enough young carers were known about or receiving support in the eight local councils areas in England they visited last year.
They said children caring for parents with a drug habit or mental health problems were particularly vulnerable.
Another report is highlighting the problems of young carers in Wales.
That report, from the Children's Commission for Wales, says more than half of young carers have felt they could not cope with their responsibilities during the course of a week.
In England, Ofsted inspectors carried out their research last November and December and spoke to 50 young carers - 37 of whom were caring for disabled parents and 13 for siblings.
The children were dealing with a range of disabilities, including physical and sensory impairments, learning difficulties, drug and alcohol-related problems and mental health problems.
'Accepting' of the role
The report found young carers were generally accepting of their role as carer and felt it made them closer to their parents than their peers.
"I don't have anyone back and I don't go out - just say I can't be bothered, it's easier than explaining," one carer told inspectors.
Young carers also said their experience had helped them deal with the practicalities of life at an early age.
"If her speech knocks out I have to lay pillows around her in case she fits," said one carer.
But older children said they were frequently late or absent for school or college and had problems getting coursework finished on time.
Of the 28 young carers at school asked, 19 said their school was aware of their caring responsibilities, but nine had not told staff.
One young carer said: "Sometimes I am late for school - they don't remember I'm a young carer. Just put up with the detention."
Number of carers 'underestimated'
Ofsted said the 2001 census figure that 175,000 children and young people in the UK provided care was an underestimate "because many families do not reveal their situation".
Inspectors found none of the eight areas examined had reliable estimates of the number of potential young carers.
Inspectors said families' reluctance to communicate with the authorities was a key barrier to identifying and supporting young carers.
"My dad don't trust anyone from social services", one carer told inspectors.
The research also found professionals often lacked awareness of the difficulties faced by young carers and did not take children's views into account when assessing disabled parents.
Only three of the 37 young carers with disabled parents said their views had been sought or included in a parents' assessment.
The report said: "Seven areas stated that many professionals... lacked insight into the impact of a parent's disability on the children and young people in the family, some of whom will be young carers."
And in three of the areas assessed, the number of children in caring roles was higher in areas of deprivation.
The inspectors said schools played a key role in helping children with caring duties.
For example, analysing absenteeism data could help reveal pupils not previously identified as having caring responsibilities.
Having a young carers policy and a designated teacher with responsibility for these pupils increased the support available.
The report cited one school where young carers presented in assemblies to make other pupils aware of the issues surrounding caring.
Chief inspector Christine Gilbert said: "Councils and their partners need to work together to identify and support young carers and their families.
"It is unacceptable that for most young carers no assessment of their own needs was conducted by children's social care professionals."
Clare Tickell, chief executive for Action for Children, a charity which has run a television campaign to raise awareness of child carers, said: "Young carers are often the invisible faces of caring.
"They can be forced to step in to meet the needs of a relative which are not being fully met by adult care services.
"We know from our work in supporting young carers that they carry a huge weight of responsibility."
The council areas visited by Ofsted were Birmingham City Council, Bournemouth City Council, Cambridgeshire County Council, London Borough of Hounslow, Nottingham City Council, Plymouth City Council, Royal Borough of Kensington and Chelsea and Swindon Borough Council.