A three-year-old required hospital treatment after becoming stuck to a toilet seat in a bowling alley which had been smeared with glue.
Lucy Richmond was visiting Bowling International in Stroud, Gloucs, with her mother and elder brother.
Her mother Annabel, 37, tried to lift Lucy off the toilet seat but found she could not move her and lumps soon appeared on her leg.
The child was taken to hospital for a check up and has made a full recovery.
"I tried to lift her off and I couldn't," said Ms Richmond. "She was just screaming and screaming.
"I had this moment of blinding realisation when I saw the lumps on her leg.
"It's just disgusting that anyone should consider that sort of thing as a practical joke.
"It's a disabled loo. They are targeting the most vulnerable people."
Bowling International director Richard Cave said the company was determined to catch the culprit.
"Obviously we very much regret the suffering this young girl and her family have gone through," he said.
"We are checking CCTV footage and have reported the matter to the police."