In advertisements, Kiddie Junction billed itself as more of an educational institute than a day-care center. It told parents that its teachers used the latest child development research to instill a lifelong love of learning in its tiny clients.

But staff members at the Des Plaines, Ill., child-care center faced a simpler question: What do you do when you can’t get a 2-year-old to settle down for a nap?

Three employees thought they had an answer, police say. They have been arrested.

They are accused of giving toddlers gummy bears dosed with melatonin, an over-the-counter sleep-hormone supplement that induces sleep.

The owner and director of the day-care center called police after finding a nearly empty bottle of melatonin gummy bears, according to Chicago CBS affiliate WBBM-TV. The owner confronted one of the employees, who allegedly admitted to giving the gummies to children without parents’ knowledge.

It was unclear how long the alleged drugging had been going on. Only four gummies remained in the 120-count bottle, police told WBBM.

Officers investigated and found that two other staff members had also been handing out the gummies to some of the dozen 2-year-olds in the center’s care.

According to the Chicago Tribune, after police consulted with the Cook County State’s Attorney’s Office, the staff members — Kristen Lauletta, 32, of Niles; Jessica Heyse, 19, of Des Plaines; and Ashley Helfenbein, 25, of Chicago — were each charged with two counts of endangering the life or health of a child and two counts of battery.

The caregivers told police they didn’t think the gummies would be harmful because they were an over-the-counter product, according to ABC News. But the Walgreens-brand gummies say on the label that they are not to be taken by anyone younger than 16.

The three are scheduled to appear in court April 4. They could not immediately be reached for comment. It was unclear whether they had hired lawyers. A woman who answered the phone at the child-care center told The Washington Post that “the director is busy at the moment.” The director didn’t immediately return a message seeking comment.

“This is just a horrible case of bad judgment,” Des Plaines Police Chief William Kushner told WBBM.

The Tribune said none of the 2-year-olds appeared to be negatively affected, although one parent reported his child was groggy after being picked up at Kiddie Junction.

The Food and Drug Administration regulates dietary supplements such as melatonin, according to the National Institutes of Health, but rules are less strict than for prescription or over-the-counter drugs. The National Institutes of Health said there have been “no reports of significant side effects of melatonin in children.”

Some companies even offer “sleep support” gummies with melatonin for children.

A melatonin overdose isn’t fatal, but it is a hormone and does have an impact on children, according to a HuffPost article on the supplement.

“With children … it can affect puberty, disrupt menstrual cycles and impede normal hormonal development,” HuffPost reported.

The Mayo Clinic also deems melatonin “generally safe” but recommends that people take it after consulting with a doctor. The hormone can negatively interact with drugs that mitigate seizures, diabetes medications and “anticonvulsants in neurologically disabled children.”

The risk to the children was at odds with the image Kiddie Junction presented to the world.

“As a parent, you have peace of mind,” the day-care center says in a promotional video, “knowing your child is in a secure building with locked entries and sign in and sign out requirements.”

Parent Edi Kulasic said he “didn’t know what to think” when he got a call at work from police.

“When they called me, as soon as they said they were at the school, my heart dropped,” he told WBBM.

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