Their motivation for allowing the cameras into their lives was simple. They knew what they wanted to do was controversial, yet they believe any parent in a similar position would do the same. They want people to judge their actions in full possession of the facts and believe the documentary will show the public that they are not monsters dabbling with nature for frivolous reasons.
Jayson and Michelle Whitaker are sensible, responsible and loving parents. Ever since their son Charlie was diagnosed with Diamond Blackfan Anaemia when he was three months old, they have followed a rigorous treatment programme for him. This programme involves regular blood transfusions and nightly treatment at home, without which he would not survive.
Charlie will have a shortened life span but the worry is that he could have total bone marrow failure at any time. This - plus wishing to spare him the rigors of the on-going treatment - is why Jayson and Michelle have been so anxious to find a cure for him. Stem cells collected from a matched sibling's cord blood would give Charlie the best chance of success in a bone marrow transplant enabling his body to make his own red blood cells so he wouldn't need treatment any more.
The Human Fertilisation and Embryology Authority (HFEA)'s groundbreaking decision to let the Hashmi family undertake treatment to select a matched embryo gave the Whitakers hope that they would also be allowed to proceed. However, unlike the Hashmis', Charlie's disorder is not inherited. The HFEA declined the application on the grounds of safety. The authority says that not enough is known about the long term effects of removing one cell from a three day embryo. If this is being done solely to benefit another, as in the Whitaker case, then it is a risk not worth taking.
Many people believe this HFEA decision was illogical when seen in the context of the Hashmi case. Both cases require an embryo to be selected. The only criteria for an embryo to be selected is that it is a match for an existing sibling. Even if the Hashmis' embryos are disease-free, they will be discarded unless they are a match for their son Zain.
Faced with the HFEA's refusal, the Whitaker family went to the US for treatment. During the making of the documentary, I was continually struck by how well the Whitakers were coping with their situation, although inevitably at times the stress and anxiety did get on top of them. They embarked on a roller-coaster ride that was largely out of their control and I hope the documentary reflects the ups and downs of their journey - the worst times and the best times. There were many hurdles to cross and I think Jayson and Michelle had to live very much in the present, not thinking too hard about what had gone before and what was ahead of them.
Fortunately, things worked out and now they have Jamie, a much loved addition to the family. His cord blood was successfully harvested after his birth and the transplant is likely to happen next year.
The family are gearing themselves up for the operation but they are dreading it. Although using stem cells from a matched sibling will give Charlie the best chance, there is still a risk that things could go wrong and I think they will find the next few months very hard to cope with as yet again things will be out of their control.
I will be interested to see how the public judges the Whitaker family. The selection of embryos to save a life takes us into complex moral and ethical areas. But I believe few parents would turn their backs on a treatment that could give their child a chance of a relatively normal life.
Rachel Coughlan is the producer of 'A Baby to Save our Son', to be shown on BBC 1 at 9 pm, Tuesday 9 December, 2003. She began filming with the family over eighteen months ago just before they embarked on their extraordinary journey.