Parents who own Fisher-Price brand infant rockers are being warned not to leave their babies in them while they are sleeping due to the chance of it being fatal.

“The U.S. Consumer Product Safety Commission (CPSC) and Fisher-Price are alerting consumers to at least 13 reported deaths between 2009 and 2021 of infants in Fisher-Price Infant-to-Toddler Rockers and Newborn-to-Toddler Rockers,” a Tuesday press release said.

“Parents and caregivers should never use inclined products, such as rockers, gliders, soothers, and swings, for infant sleep and should not leave infants in these products unsupervised, unrestrained, or with bedding material, due to the risk of suffocation,” it added.

There have been multiple reviews and reported incidents on the rockers, of which 17 million have been sold since the 90s. There is no official recall on the rockers.

The CPSC reminded parents in the release that the best place for infants to sleep is on “a firm, flat surface in a crib, bassinet or play yard” and that “infants should always be placed to sleep on their back.”

The CPSC also recently finalized a rule that will require infant sleep products to have a sleep surface angle of 1- degrees or less. This rule will go into effect on June 23, 2022.