Twelve days after they went swimming in Crescent Beach, three-year-old Millen Adamson of White Rock and her one-year-old brother, Blane, were still covered with vivid red spots on both legs.
"It's actually a lot better now," mother Dana Adamson told a Peace Arch News reporter last week.
It started with a trip to get some fish and chips from a beachside vendor in Crescent Beach.
Once there, the chidden wanted to play in the water, and their parents saw no reason to stop them.
"There were 20 other kids in the water," Father Paul Adamson said.
Later that same day, he says, Millen began to experience symptoms.
"Daddy, my legs are really, itchy, itchy, itchy," she told him.
By the next morning, both children had a severe outbreak of "pimple-looking" lesions below the waist.
It was swimmer's itch.
According to HealthLink BC, the condition is not life-threatening, but it can be quite unpleasant.
The temporary, itchy rash is caused by small worm-like parasites, called schistosomes, found in the bodies of water snails and in the bloodstream of aquatic mammals, ducks or other waterfowl.
When swimming near the water surface in search of these hosts, schistosome larvae sometimes mistakenly get on people's skin.
After a person leaves the water, the microscopic larvae burrows under the skin, dies almost immediately and can cause an allergic reaction that results in the itchy rash.
It can be painful, especially for small children.
"We went through two nights of hell," Paul Adamson said.
A doctor said his daughter was old enough to take an antihistamine to reduce her symptoms, but his son was too young.
"It's a bit of a nightmare," the father said.
According to Fraser Health, swimmer's itch is fairly common in Crescent Beach and occurs every summer when the weather gets hot.
The best preventative is to vigorously towel off on leaving the water.
"We didn't have a towel with us and that was our mistake," Paul Adamson says.
The parents said they didn't know the problem existed at the beach, and while they have been told by the City of Surrey that warning signs have been posted, they said any signs were not obvious to them.
Dana Adamson, who has had her own brush with swimmer's itch, says she would have noticed any reference to it.
Surrey parks manager Owen Croy said the warnings are there.
"It's been added to all the signage."
Croy says there has only been one complaint of swimmer's itch at Crescent Beach reported to the city this year.
As well as drying off briskly with a towel immediately after leaving the water, Croy noted people can reduce their risk by applying waterproof sunscreen, and rinsing off in a shower.
Treatments for the afflicted includes cool compresses, calamine lotion and antihistamines.
For more information on swimmer's itch, visit www.healthlinkbc.ca/healthfiles/hfile52.stm