This week a national newspaper splashed a photograph across its front page that would tug at the heart strings of even the meanest of Christmas Scrooges.

It showed five little girls in care who will be spending Christmas apart. Their one wish was to find a new foster mum and dad who had the time, space and energy to care for all of them together.

Christmas is all about people spending time in the warm bosom of their own families but for children in care it is very often a time which exaggerates the feelings of being torn away from those nearest and dearest to them.

For the thousands of foster families who look after these youngsters, it can be an emotionally charged time which requires the diplomacy of an ambassador in a war zone.

But for all the stress of caring for other people's children during the festive period, it can also bring its own rewards.

Rudd and Deborah, from Stoke-on-Trent, are foster carers to two children aged five and six who have never enjoyed the magic of leaving stockings for Santa and the excitement of opening the presents from him on Christmas morning.

For them this year will be the first time they have ever had a traditional Christmas dinner and when Rudd and Deborah brought home a huge Christmas tree, the youngsters were mystified. "They thought it was for the garden," said Rudd.

And the children were thrilled when their foster parents turned up to watch them in the school Nativity - the first time anyone had bothered or been able to show an interest in them in this way.

The excitement built even further when Father Christmas, helped by the local Round Table, called round to see the children at their foster home.

However, for all the enchantment and excitement of their first ever 'proper Christmas', it is still a stressful time because it will remain, for them, a period of loss and separation.

Rudd's foster children come from a family of seven who are split among various foster homes.

Because of the manpower logistics of social services, it has only been possible for these children to meet up altogether with their mother for and an hour and 30 minutes.

And not for these children a cosy family reunion in a home environment on Christmas day. The gathering of this clan was only possible in the functional surroundings of their local social services offices and under the supervision of professionals paid to be part of their lives.

This was on December 22 and these children will not now meet up again until January 10. As Rudd pointed out: "Nineteen days when you are five can seem like a lifetime."

And despite the excitement of the reunion, the event inevitably upset the children when it had to end, and they left saddened in the knowledge that they would not be seeing each other on Christmas Day.

The utter poignancy of their situation was illustrated when the foster carers asked the children what they wanted as presents.

"They didn't know," said Rudd. "But in the end all of them asked for the photo that they had had taken of them together at school.

"They are coping with it very well but it is hard. They are left thinking 'Do I kick up about it and ruin the Christmas I am going to have, or do I just shut up about it?'"

Caring for foster children over Christmas also affects the wider family and for Rudd and Deborah, their own children, aged 12 and nine, were worried that the two extra additions would diminish the family's usual Christmas routines.

"They were also very materialistic at first and worried who was going to pay for all the extra presents," said Rudd.

The family, like all foster families, gets an allowance to cover the cost of presents and they have also been touched by the spontaneous genorosity of people in their neighbourhood who have come round bearing gifts for the foster children.

The implications for the extended family is a common difficulty for foster families.

Carolyne Carter has just retired from fostering but has shared her family Christmas with foster children for 17 out of the past 20 year during which she has looked after more than 90 children.

For her, the problem was always her own mother, who never made any bones of the fact that she did not like her daughter fostering.

So, while she would turn up with fabulous presents for her own grandchildren, the foster children would tend to receive something rather smaller and less impressive.

"You try to do it very equally but it can never make up for what they are missing," she said.

It is often the whole smothering familyness of Christmas than can be so difficult for fostered children.

Carolyne comes from a large and close-knit extended family who all descend on her Wiltshire home in Chippenham for Christmas Day lunch.

"I've had children who haven't been able to face Christmas lunch because they just cannot cope with sitting round the table. And they spend the whole day in their bedrooms and eat the meal on their own, later."

It is a scenario that has also faced foster carer Darren Beamman of Redbridge in London, who believes it is something, older children tend to find harder to deal with than younger children.

On these occasions, Carolyne says she makes the point to the fostered child that if they want to retreat from the frenetic commotion of a family occasion, they can and there is nothing wrong with wanting to do that.

"It can be very difficult. Everybody has such high expectations at Christmas but that is not to say I have not had some lovely moments."

She recalls a time when she took in an eight-year-old girl at the beginning of December and who was all set to spend Christmas in care.

Social services duly provided the money to buy her presents but just before Christmas, it turned out she was able to return home - along with the whole raft of gifts, courtesy of social services, which her mother would not have been able to give her otherwise.

However, not all birth parents can be so grateful for their children having a little festive joy bestowed upon them.

Rudd said he had heard of instances where children have returned home with an array of new toys after spending Christmas in care, only for the gifts to be taken from them by their cash-strapped parents and sold at the local car boot sale.

And Carolyne has experienced times when a fostered child will phone their parents on Christmas Day and excitedly tell her what they received and end up disappointed by the parent's reaction to the discovery that their child has received gifts that they, themselves, could not possibly have afforded if the child had had Christmas at home.

Carolyne, like Rudd, has had children who have never had a birthday cake or a stocking. But as nice as it is to provide all this for foster children for the first time, it can, in itself, present difficulties.

As Carolyne pointed out: "They may be going back to their family where they won't get all this."

What most children really want for Christmas, though, is simply to be with their own family and this feeling is just as strong among children whose parents have been far less than perfect.

"It doesn't matter how bad an upbringing they have had, they still want to see mum and dad," said Rudd.

"It's just not like a Bing Crosby Christmas..."