Charlotte Duberry, who is 14 months old, must wear a helmet 23 hours a day to try to correct the growth of her skull.

She suffers from brachycephaly, a flattening of the back of the head, which affects 33 out of 10,000 babies and happens because bones in the skull are soft until the age of one.

Dad Ian, of Thompson Way, Kettering, said: "This is something that is classed by the NHS as a cosmetic treatment, which could not be further from the truth. We weren't aware of the syndrome until it was too late and now Charlotte faces wearing the helmet for at least nine months."

"We went to London to get the cap fitted on December 21 and we have been told to expect the earliest date to get the helmet off to be August."

Charlotte's mum Amanda noticed her daughter's head was flattening at the back when she was five months old.

After a meeting with their GP, the family was told there was nothing that could be done on the NHS.

The family only realised treatment was available after Charlotte's grandmother found the website www.ahead4babies.com which helps correct abnormally-growing skulls.

Charlotte went for her first scan in London on December 11, to take head measurements for the helmet.

The family has been holding fundraisers to pay for the treatment.

A spokesman for Northamptonshire Primary Care Trust said: "There is an increasing tendency to use a special moulding helmet to treat severe positional plagiocephaly and brachycephaly.

"As yet there is little good scientific evidence to support how effective this method is."