UNITED NEWS INTERNATIONAL (UNI) — Health experts are advising Facebook to shut down its new child-friendly chat room app.

The app, called Messenger Kids, is a simplified version of Facebook Messenger with parental controls.

Facebook said it has worked with families to develop it. However, not everyone is on board.

A U.S. coalition of health care professionals named Campaign for a Commercial-Free Childhood wrote a letter to Facebook CEO, Mark Zukerberg on Jan. 30, calling the app “harmful” and said it will, “undermine children’s healthy development.”

The experts say young children do not fully understand privacy and what is appropriate to share, and it is, “irresponsible to encourage children as young as preschoolers to start using a Facebook product.”

Facebook, however, says the site was set up to give children a platform to communicate with childproof privacy and it has received good feedback from parents since its release in December.