Tonsillitis is a common childhood ailment that in most cases can be treated with over-the-counter medicines. But, the condition turned deadly for a British toddler after a doctor told his parents to “wait for the medication to work,” the Daily Mail reported.

Joseph Seevaraj, 3, was found dead by his mother and father at their home in Hove in East Sussex, England, on Jan. 20 of this year.

The little boy had been severely ill the night before, with vomiting and diarrhea. His parents called their physician, but the doctor told them to wait for the antibiotics to work, which had been prescribed days earlier, according to the report.

At a hearing Thursday, the coroner described the “gross errors” made in his treatment.

“He needed basic medical attention,” she told the panel. “I am satisfied there is a clear connection between this gross failure and his death.”

The coroner ruled Joseph had died from septicemia, a potentially life-threatening infection, which occurred as a result of tonsillitis, the Mail reported.

The court was also told that if Joseph had been taken to hospital he would not have died.

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