Harry Barker cannot tell doctors about the crippling pains he has even when on painkillers more potent than morphine.
He only has a few words because of a developmental delay but his parents see it in his eyes when even the most powerful medication barely touches the edges.
Harry, 9, is one of hundreds of children with chronic pain who slip through the cracks because there is no dedicated paediatrics pain unit at Princess Margaret Hospital.
Parents like Harry's mother Tracie Barker say they often get the run-around to see specialists and are sent home with potent opiates.
In desperation, last month she pleaded with PMH for a unit with a chronic pain specialist so children did not suffer unnecessarily.
Harry has an undiagnosed syndrome, thought to be a genetic metabolic disorder, and has frequent seizures triggered by pain. He can only walk a few steps and is often in so much distress he scratches until he bleeds.
On his frequent visits to PMH, he cannot get to the pain team without a referral from a doctor after a nurse assesses him. "By then he's writhing in pain and very distressed," Mrs Barker said.
She said she and husband David still held PMH staff, who did all they could, in the highest regard.
Julia Sutton, whose arthritic daughter used PMH until the age of 18, said the service for children was vastly different to that for adults.
She said her daughter's pain was not taken seriously at PMH yet they were often sent home with strong painkillers.
"PMH's emergency department doesn't deal well with children with chronic pain," she said.
"There are doctors on a roster as a consulting pain team but in our experience they are rarely called."
Pain expert Dr Stephanie Davies said there was a huge gap in services by not having a child pain unit.
Health Consumers Council WA head Michele Kosky said the management of chronic pain in children was under-resourced at PMH.
A PMH spokeswoman said a dedicated pain management service could only be considered with the future assessment of all clinical demands for new services.