When your child is upset and on the verge of making a scene in the cereal aisle, it can be easy to fill their hands with a smartphone or tablet so you can keep filling your cart.

A new study, however, says this quick fix may hinder your child’s emotional development.

Canadian and Hungarian researchers followed 265 Canadian families with preschool-aged children for a year, looking at three aspects of self-regulation, a skill children develop in early childhood.

The researchers looked at anger management, or how a child handles feelings of anger and frustration; effortful control, the ability to focus and regulate behavior; and impulsivity, which is how quickly they act without thinking.

The families completed a questionnaire that assessed their media use, child behavior, and parenting stress at the start of the study and again a year later.

The results showed that greater use of devices as digital pacifiers had a negative effect on children’s self-regulation skills and prevented them from dealing with emotions on their own.

Parents who frequently used digital devices as a calming tool reported having children who struggled to manage their anger and exhibited less ability to focus and self-regulate.

Children with poor anger-management skills at the start of the study were more likely to have parents who were reliant on digital devices a year later, suggesting a cycle that further harms children’s long-term development.

In short: the next time your toddler throws a tantrum, think twice about handing them a device, unless you want to deal with an extra moody teen down the road. The grocery store will still be there tomorrow.