The mother of a severely disabled boy is hoping the challenge of jousting, crawling through mud and riding a “flume of doom” will help raise money for a charity which has given her so much support.

Sarah Edser, 33, of Henderson Drive, Dartford, admits she doe not know how much time she has left with eight-year-old Charlie, who needs round the clock care to monitor his life-threatening seizures.

He was diagnosed with Dravet Syndrome, a catastrophic form of epilepsy so rare it affects just one in 500 sufferers, five months after he was born.

According to experts, only one in five with the incurable condition will live to be an adult.

Charlie is largely non-verbal only using yes and no to communicate with his family and requires an oxygen cylinder at night to help him sleep.

While his younger brothers Henry and George are running around, Charlie’s ability to walk is on par with a toddler while he is prone to frequent chest, ear and urine infections.

Sarah admits time with her son is precious, especially after two families she is close to suffered child bereavements.

She said: “You have to be matter of fact about it, that’s the reality we face.

“He is not a typical eight-year-old; he operates roughly as the same as a toddler between 15 and 20 months.

“Charlie is the eldest of three boys and when you see his brothers overtake him in every possible way it is hard to see but on the other hand there are so many times I’ve nearly lost him, it is unbelievable the way he fights despite everything he faces.

“He is such a happy boy, he doesn’t ever moan or complain and he always has a smile on his face.

In December 2012, Sarah set up Charlie’s Champions with the help of her sister Claire, relative Hayley Turner and friends Stacy and Tonia Cummins to help raise money for Dravet Syndrome UK, the charity that supports Charlie and other sufferers.

Proceeds are donated towards funding research to help find a breakthrough to offer children with the disease hope.

The group has held more than half a dozen fundraisers in that time including a bungee jump, sponsored walks, 1980s and garage music nights and a family fun day.

On Saturday, August 8 a group of 10 will participate in the Gauntlet Games near Brighton to raise more money, with £8,000 collected so far.

Sarah added: “The idea is that we will always champion for Charlie and put him first.

“Charlie has taught me so much about what is important in life, to appreciate everything you have and that the little things are really the big things.

“Every day Charlie amazes me and makes me proud with all that he goes through, deals with, overcomes and achieves – he is my hero.

“I feel very privileged to be his mum.”

To support Sarah visit the group’s Charlie’s Champions Fundraising For Dravet Syndrome UK Facebook page or www.justgiving.com/Charlie-s-Champions.