Later in 2020, Ms. Lavelle also complained to the board, describing how she had been traumatized by her daughter’s tongue-tie release.

The breastfeeding board, which reports its disciplinary decisions, has taken no action against Ms. Henstrom. A board spokeswoman, Susan Brayshaw, declined to comment on the complaints, citing a confidentiality policy. “Some complaints take much longer than others due to the nature of the allegations and related investigations,” she said.

Since 2002, the board has revoked the certifications of only three lactation consultants.

Ms. Lavelle also filed a complaint against Dr. Zink with the Idaho Board of Dentistry. The board collected medical records and statements from Ms. Lavelle and Dr. Zink. Dr. Zink told the board that June’s procedure was “uneventful,” but that an extremely small percentage of patients do not respond well to the procedure. He said none of his hundreds of frenulum patients had complained before.

The board’s executive director informed Lavelle via email that the group “did not believe further investigation was warranted.” He found that Dr. Zink was not to blame.

Late last year, Ms. Henstrom recommended loosening the tongue, lips and cheeks for a baby named Vivi. Sitting in Dr. Zink’s waiting room a few days later, Vivi’s mother, Aubrey Nobili, could hear her baby’s screams over the muffled hum of a noise machine.

When Mrs. Henstrom carried Vivi back to the room, the crying baby couldn’t catch her breath. Mrs. Nobili approached her daughter and smelled burnt flesh.

Vivi never breastfed again.

Six months later, a specialist at St. Luke’s evaluated Vivi because she had difficulty swallowing and sometimes choked while drinking from a bottle. The specialist later wrote in her medical record that her problems were “probably due” to the laser surgery.

Ms. Nobili is a homemaker and her husband, Ryan, works at Costco. They have four other small children. They said they racked up more than $5,000 in credit card debt to pay for Vivi’s feeding therapies.

He turned 1 year old in November. Her family decorated her house with red and pink balloons and dressed her as a strawberry.

Only one thing was missing: a birthday cake. Vivi still can’t eat solid food.