To see Karen Simpson bouncing a smiling baby on her knee they look like any other happy family.

But the baby boy isn't Karen's son, he is one of the children she and her husband are fostering.

Although Karen is quick to explain that any child in their care is treated exactly the same -- as part of the family.

Karen and Richard Simpson live in Keighley and as well as having three children of their own, they have been foster parents for five years.

Mrs Simpson explains why her family got involved and the difference it has made to their lives.

She says: "Over the course of five years, we have fostered 15 children in the nought to four age range and we have really enjoyed it -- however difficult it can be, it is very rewarding

"We have three children of our own -- two daughters aged 14 and ten and a son who's 12. So there are the usual arguments of a normal family, but from the minute a child comes here they are treated as part of the family and it is so rewarding to see them develop.

"Just from the very nature of what we do, when children come to us they can sometimes be unsettled but just watching them change and become happier is amazing.

"They are all special and for what ever reason they need looking after. If they weren't fostered like this what kind of start would they have? Where would they go?"

Mrs Simpson says that her family gets very attached to some of the children -- especially if they have come to her very young and don't leave until they are toddlers.

She has pictures of every child they have fostered and the family sends each of them a birthday card and Christmas card every year.

"We have had them come as young as three hours old and it is hard to say goodbye when the time comes, but at the end of the day you are making people happy. It is important for the children to be looked after and then they go on to be adopted or re-united with their families," she says.

Mrs Simpson continues: "At the end of the day they become ours, they are accepted into our family and we all get so much out of it."

She says that she and her husband explained to their biological children about fostering and that the children are happy with it.

"My children haven't had any problems with it -- when it comes to the foster children leaving they ask if we can adopt them -- but I'm not old Mother Hubbard," she adds.

She adds: "My kids love it but its essential to talk to them and explain what's going on.

"It has opened the eyes of my kids. They are much more patient and understanding. It has shown them about real life and taught them about caring for other people."

Mrs Simpson says that she has had to look after babies in the past who were drug dependent.

But she explains that foster carers receive full training and excellent continued support from social workers, and says the workers guide and advise throughout, so carers are never on their own.

At the moment the family is fostering three boys -- a four-year-old, a two-year-old and a six-month-old.

She says: "The two older boys are being adopted at the moment and the look on the four-year-old's face when I told him was priceless. He just beamed.

"He is so excited to have a new mummy and daddy and has been taking in pictures of them and his new bedroom to school.

"It's that kind of response that makes me proud -- proud and very, very pleased I have been a part of their road to happiness."

The fostering service in the Bradford area currently has 177 families on its list to foster 338 children.

Andrew Walker, the service's senior practitioner for recruitment said a large pool of skilled and well-trained foster carers were constantly needed.

He explaines: "We want more carers so we have the chance to match children to families in a way which best meets the needs of the child.

"We need families of every kind -- white, Asian, African Caribbean and dual heritage. Also some children find it easier to live in families where there is just one carer as they find it simpler, so we're keen to hear from single applicants.

"Some children need to be with other children, others need to be the only child in a household.

"Carers who have grown up children can make the most of their experience and help children through what may be a difficult time in their lives.

"We also want to hear from carers who are interested in looking after teenagers, as well as pre-school and primary age children.

"Fostering children is rewarding; you get paid and trained but you don't need your own house or special qualifications.

"You can be single, married or living as a couple."