A toddler who had the most misshapen head doctors had ever seen has undergone pioneering surgery to prevent her brain from being squashed. Three-year-old Kaydence Theriault  and her fellow triplets Taylor and Kaylin were all born with Crouzon Syndrome, which causes the baby's head to become misshapen.Kaydence had the most severe form doctors had ever seen because her skull was shaped like a cloverleaf.She needed life-saving surgery to ensure her brain didn't become damaged. A team of expert cranio-facial surgeons came together to save her, and now Kaydence and her siblings are like any playful toddlers who will celebrate their fourth birthday in December. They are suffering no health issues or learning problems and are catching up in height with other youngsters.Their mother Bobbie Jo, 38, of Indianapolis, said: 'The doctors have been amazing.'When Kaydence was born no-one knew if she would survive. But thanks to their incredible talent we have a normal healthy daughter and we can't thank them enough.'Crouzon Syndrome is a genetic condition that causes the plates of a baby's skull to lock in position too early, before the brain has had chance to grow.Most children born with the condition have surgery before they are 18 months old to separate the skull before it fuses.But Kaydence's condition was so severe the bones were already joining together, pushing her head into an odd shape at the top and sides, like a three-leaved clover.Mrs Theriault had no idea there was a problem until her 20-week scan showed one of the triplets had a deformity.She said: 'When the doctors told me about Kaydence having a cloverleaf shaped head, I couldn't picture that. I have never seen it before so I had no idea what to expect.'She and her eldest son Jayden, eight, also have Crouzon Syndrome, which Mrs Theriault inherited from her father. But each of them has a milder form and underwent small operations just before they were one.Her husband Jason said: 'The shape of Jayden's head started changing and that's when we and the doctors realised he needed surgery. He was in hospital two or three days and then he was home and that was the end of it and he was completely fine.'That's one of the main reasons why we had decided to have another child. I didn't want Jayden to grow up without a sibling.'The Theriaults were overjoyed when they discovered they were expecting triplets and say they had 'no idea' that their babies would be in danger of having a life-threatening form of Crouzon.Mrs Theriault said: 'Jayden had been fine so I thought it would all be okay.'Her husband added: 'But when Kaydence came out I knew she would be the one who would have the most problems. I was just absolutely astounded at the severity of it.'Kaydence needed emergency surgery to open up her skull at two months old, as soon as she was strong enough, so her brain would have room to grow.Then, three months later, a team of expert surgeons came together at Peyton Manning Children's Hospital in Indianapolis to perform a delicate operation to reshape her head.World famous cranio-facial surgery Dr Kenneth Salyer, from Texas, was brought in to help with the surgery, which took place in May 2010 and lasted eight-and-a half hours.Neurosurgeon Dr Ronald Young said: 'The only way to reshape the head is to take that bone apart and put it back together in a different shape and that's what we did.'Mrs Theriault, a health admin worker, said: 'I was scared, I was worried, I was sad. I wanted it to be over, I just wanted to see her. I didn't know how such a small baby could cope with being under anaesthesia for so long.'Dr Young added: 'Our main worry was bleeding. This was a very small child and we were working over a very large blood vessel. After that it was exposing the brain to possible infection or damage during the surgery.'To their relief, everything went well and Kaydence made an incredible recovery and was out of hospital and back with her siblings in a matter of days.Her cloverleaf shaped head was transformed, and with the help of smaller follow-up surgeries, she is now virtually unrecognisable from how her appearance as a newborn.Taylor and Kaylin, who had a milder form of Crouzon, underwent their surgeries at seven months old and are also doing well.Each child underwent physical and speech therapy to help them catch up with other three-year-olds because of their time spent in hospital. But the girls are expected to start nursery soon and will have no lasting effects.When the triplets are older they will be able to have plastic surgery to help make their face and eye shape more normal if necessary.As a child, Mrs Theriault admits she was teased by schoolmates because of her mildly protruding eyes, but she believes it made her a stronger person and better able to help her own children.Her husband said: 'I've know Bobbie Jo since she was 14 and she has always stood up for herself and never backed down from anybody.Mrs Theriault added: 'Children are going to be children. Bullying is everywhere no matter who are. All three of the triplets will probably come across somebody who is going to bother them. But if they do get called names they will have me to help them.'When Jayden started school he said some of the kids made fun of his eyes. But now he has learned about Crouzon Syndrome and tells people about it. That has helped him stand up for himself.'We're so happy they can have a normal life," said Bobbie. Jo. "I love those doctors for what they have done for my family.'The story appears in Unlock My Skull: Body Bizarre at 10pm on Monday December 2nd on the Discovery Channel.(dailymail.co.uk)ANN.Az