A 5-year-old southwestern Michigan boy has died from medical complications following a routine tonsillectomy.

Hunter Mosher of Constantine, about 30 miles south of Kalamazoo, went to Watervliet Community Hospital on May 8 for an outpatient procedure on his swollen tonsils.

He was readmitted the next day when his mother noticed that he was exhausted and wasn't swallowing.

Erin Mosher tells the Kalamazoo Gazette that her son was taken to Three Rivers Hospital, where his condition deteriorated and he lost consciousness.

His mother said the procedure was done at a doctor's suggestion to alleviate drainage in his ears. She was told the surgery was "routine" and doesn't know what went wrong.

"There was nothing wrong with him before that," Mosher told a local ABC News affiliate. "The surgeon knows that there was something from his surgery that did this and killed my son."

Three Rivers Hospital transferred to Hunter to Bronson Methodist Hospital in Kalamazoo but he never reawakened.

He died last Saturday.

Ray Cruse, chief executive of the Watervliet hospital, says everyone who works there is deeply saddened by the child's death.

The Associated Press contributed to this report.