For Naomi Marek, whose son Max has a life-threatening epileptic condition, Camp Simcha has made an enormous difference. It's given her friends who understand, a community to support the family and allowed her other son the chance of a normal childhood."We wouldn't have survived without this lot," she says.
Living in the Bedfordshire countryside, she and husband Adam felt isolated when Max, now nine, was diagnosed nearly three years ago.
Partially brain damaged as a result of the seizures, he has been in hospital some 50 times since and is on huge quantities of drugs and steroids. This week he is back in Great Ormond Street Hospital, another worrying time for the family.
"When this happens the world keeps on crashing around you but you are no longer part of it," Mrs Marek confides. "My friends found it difficult to cope and hard to talk to me.
"But you become normal when you meet people in similar situations. It's not just the bowling trips, Legoland outings, or summer retreats. It's having someone to accompany you to doctors' appointments when your husband is stuck at work - someone to turn to on the bad days.
"Last year Max had a lumbar puncture, which obviously was very distressing for him - he was crying and screaming. Then Gideon [his Camp Simcha big brother] arrived with a big teddy bear for him and other volunteers came too. Within 20 minutes he'd stopped yelling. We had a family there."
Mrs Marek knows another mother nearby whose son was diagnosed with a brain tumour two years ago but still cannot bring herself to leave the house. Without Camp Simcha, she might feel likewise. "You crumble until you get support," she says.