The family of an eight-year-old boy suffering with a serious genetic condition are fundraising to take him on the holiday of a lifetime while he can still walk.

William Hagg, eight, from Hall Road in Norwich, was diagnosed in November with muscular dystrophy which causes weakened muscles and leads to increasing levels of disability leaving some sufferers in a wheelchair.

Some types of muscular dystrophy eventually affect the heart or breathing muscles, at which point the condition becomes life-threatening.

William, who studies at Free School Norwich, has always suffered with mobility problems and cannot walk more than 200 metres without collapsing.

The youngster cannot run and has never been able to jump in a swimming pool ride a bike or explore a climbing frame.

His parents, Vanessa and Gary, who also have a two-year-old girl called Eleanor, want to raise £4,000 to go towards a family holiday at the Florida Walt Disney World Resort this June.

They revealed the plans to their 'kind and loving' son on Christmas Day and a JustGiving fundraising page was set up online by William's grandmother, Val Brookes, as a surprise.

So far just over £2,300 has been raised and an additional £1,000 has been privately donated to the family fund.

Mrs Hagg, 40, a hotel group sales manager, said: 'We got the diagnosis of muscular dystrophy on Black Friday which meant it really was a Black Friday for us. I was shocked when I got the diagnosis - we are still in shock. We need to get him to Disney World while he is still moving.'

She added: 'I was completely blown away by the response to the online fundraising. The support has been amazing and makes you realise what a special little boy he is. The fundraising is for him, not us.'

Teachers at his pre-school first flagged up potential mobility problems when William was just four.

He was initially diagnosed as being flat-footed and suffering with hypermobility, where the body's ligaments are too flexible, around 18 months ago.

But a blood test just before Christmas which revealed increased levels of the creatine kinase enzyme prompted the muscular dystrophy diagnosis.

Mrs Hagg said: 'Everything changes after the diagnosis. William's life's dream was to be a racing driver and it is heartbreaking to know he won't be able to achieve his dream.'

William's father, Gary, 48, a civil servant, said: 'As a parent you want the best for your kids. It is about trying to readjust your expectations so things are achievable for him.'

The youngster who enjoys cars, music and arts and crafts, will receive hydrotherapy treatment and physiotherapy.

He does not use a wheelchair yet but the family will receive one soon as he needs to be carried when he cannot walk.

To donate visit www.justgiving.com/crowdfunding/getwilliamtoDisney