Figures have revealed that boarding - when patients are admitted or moved to departments that do not usually look after their medical problem - is used regularly at the hospitals for sick children in Glasgow and Edinburgh.
Over a year, there were more than 950 occasions when medical patients at the Royal Hospital For Sick Children Sick, Edinburgh, had to board. There were a further 840 at Yorkhill.
The Herald obtained the figures using Freedom of Information legislation amid anxiety among doctors and nurses about the capacity of the new children's hospital being built in Glasgow.
Serious concern about the use of boarding in adult hospitals because of bed shortages has also been raised this year. Scottish Government research found patients were more likely to die if they had to spend time being nursed in the wrong department.
Doctors talk about undertaking "safari rounds" - trying to find patients under their care who have been displaced - and there is evidence that adult boarders spend significantly longer in hospital than those looked after in the right wards.
On average, Yorkhill medical patients were logged as being in non-medical beds 68 times per month between July 2012 and August this year, while for those in the Royal Hospital For Sick Children, Edinburgh, the figure was 71. At peak times there were 151 boarders in the capital.
Dr Zoe Dunhill, former clinical director of the capital's sick children's hospital and a committee member for charity Action For Sick Children Scotland, said when youngsters with long-term conditions were placed on different wards it could be unsettling for their families.
She said: "It is a parent outside their comfort zone if their child has complex needs because they do not know the staff. Over the years they build up relationships, which are very valuable. Parents will say, 'He is just not happy, they do not know everyone.'"
The number of beds in Yorkhill has dropped over the years from 270 in March 2006 to 229 in March this year. This summer bed numbers were lower than last summer, 223 for July, against 231 for July 2012. However, the number of medical admissions increased almost 50%, from 798 to 1193.
One hospital source, who did not wish to be identified, said: "This places considerable pressure on staff to discharge patients. It should also be seen in the context of a steadily rising Scottish birth rate and the new, smaller Royal Hospital For Sick Children now being built at the Southern General site in Glasgow. Many of us are concerned it was planned on outdated population models and may not be fit for purpose, let alone future-proof."
The source added that the location of the new hospital may also mean families who would previously have attended the Royal Alexandra Hospital, Paisley, "vote with their feet" and bring their children straight to the new unit.
The number of births in Scotland rose for six successive years from 2002, but has decreased a little in recent years. While medical advances mean sick children can be sent home from hospital sooner than in the past, more infants with complex medical problems survive today and have conditions that trigger regular hospital stays.
Dr Dunhill said hospitals could be designed to allow flexible use of beds and stressed the way beds were used had to change during the year in children's hospitals because of a surge in cases of the respiratory infection bronchiolitis during winter months. She said it was important these patients were kept together as the virus could be very infectious.
NHS Greater Glasgow and Clyde said a total of 256 beds were planned for the new children's hospital.
The health board said: "The number of patients boarding in hospitals across Scotland varies considerably from year to year and the Royal Hospital For Sick Children [Yorkhill] is no different.
"The bed model for the new children's hospital has been agreed following careful planning with medical and planning staff and we are confident our bed numbers are appropriate."
A range of measures to improve the flow of patients through beds have been undertaken at Yorkhill and are planned for the new hospital. It will have a 20-bed assessment ward, double the current size, to reduce the number of patients admitted to wards.
NHS Lothian did not provide bed numbers for its sick children's hospital.
The board's associate divisional medical director for children's services, Dr Eddie Doyle, said: "We recognise that boarding patients is not ideal but it is sometimes necessary in order to manage capacity.
"In winter months, the pressure around emergency admissions is largely driven by respiratory conditions. Those with this type of illness typically need to be in isolation in individual cubicles. Last winter saw an increase in the prevalence of winter illnesses, particularly respiratory conditions."