Kerry, a softly-spoken 33-year-old, admits: "The sight of Hayley as our bridesmaid was absolutely heartbreaking. I didn't think it was possible for a mother to feel so proud as I did then. I never thought I would see Hayley so happy and so beautiful."
"She was such a perfect baby - but when she was first diagnosed with this awful disease, I honestly couldn't see any way forward.I would wake in the morning and think of getting in the car with Hayley, driving somewhere quiet and feeding a hosepipe from the exhaust in through the window. I thought, we would both die painlessly."
"The diagnosis was so terrible that I could see no future for us at all. Mark and I had been ripped apart. Suicide - and taking Hayley with me - seemed the only way out. I would watch Hayley while she slept and feel such pangs of love for her. Then I'd be hit by shock, worrying what her future held. When she was born, she was so beautiful, just like any other baby, and our future as a family seemed so assured. "But since she was diagnosed, life has been simply terrifying."
Now, though, there is hope. The family have flown to America, to Boston, for pioneering treatment which may stop the ageing process and save their daughter's life.Their extraordinary battle began ten years ago when Kerry, then a cook, met carpenter Mark Okines, now 44. Two months later, she discovered she was pregnant. She smiles at the memory.
"I loved Mark and really wanted a baby. So, although it was early on in our relationship, it felt totally natural and we were delighted." The pregnancy was completely normal, and when Kerry went into labour just three days past her due date, there was nothing to suggest their baby would be anything but healthy.
Kerry says: "It was a long labour, lasting four days, but when Hayley was born I forgot about the pain in an instant. She weighed 6lb 6oz, and with her fine blonde hair she was simply gorgeous. She gazed up at us with those beautiful big blue eyes and both Mark and I just fell in love with her. We were instantly besotted."
TO BE CONTINUED