Hospitals in Dublin say children in care have spent months in their wards in the past year while they waited for the Eastern Health Board to find places for them.
They include two brothers, aged four and five years, who left Tallaght Hospital in December after living in its wards for three months, although there was nothing wrong with them.
A young child also spent months in Our Lady's Hospital for Sick Children, Crumlin, in the past year.
At least two children under two years of age spent a month each in the National Children's Hospital, Temple Street.
Social workers in the three children's hospitals say the development of young children is at risk and the experience makes older children withdrawn or aggressive.
The Eastern Health Board said last week that "there are no children currently in the children's hospitals in Dublin as social admissions". Later in the same statement, however, the EHB admitted that social admissions - as the practice of admitting healthy children to hospital is called - did occur.
Less than 24 hours after the EHB issued that statement to the The Irish Times, two children were admitted to Temple Street hospital as social admissions.
Requests from hospitals to accept such children come from the gardai at night and at weekends when health board social workers are unavailable (except for the out-of-hours service for homeless children aged 12 and over).
One child was admitted to Temple Street last year when a fostering placement broke down. Others included children with special needs, admitted to give their parents a break, because of the shortage of respite places.
Some requests come from EHB social workers, themselves unable to find places for children.
"We have had a number of very worrying situations," said Ms Brenda Mehigan, head social worker at Tallaght Hospital. The most recent instance was that of two brothers, aged four and five, who were in the hospital from September to December. Such admissions, she says, "break all the rules".
Ms Bernie Price, head social worker at the National Children's Hospital, Temple Street, said an analysis of 135 social admissions to the hospital from 1995 to 1997 showed that only a minority of children left the hospital in four days or less. Ten per cent remained in the hospital for one to four months and 3.5 per cent for four to 12 months.
The problem, she said, highlighted the need for a full health board social work service outside normal hours and for more emergency fostering and residential places.
Ms Mary Heffernan, head social worker at Our Lady's Hospital for Sick Children, Crumlin, said 18 children were admitted to the hospital as social admissions in the first half of last year and one child was there for "months and months".
In 1996 and 1997, a total of 58 such children spent about 1,000 bed-nights between them in the hospital. She found the practice "very disturbing".
Ms Heffernan said that two-thirds of the children admitted in emergencies were known to the health boards as children who might be at risk. Had there been effective intervention, the children would not have ended up in hospital.
The EHB said it "favours establishing an out-of-hours service for all children aged up to 18 and is currently in discussions with staff on this matter. A number of foster families have been recruited to provide care in an emergency for this age group when the current service is expanded." An emergency short-term residential home will open next Monday, it said.
Questions faxed to the Eastern Health Board by The Irish Times included one on whether healthy children had been hospitalised in its adult hospitals in Cherry Orchard, Loughlinstown and Blanchardstown. This question was not answered in the reply from the EHB.