Hurray! The Department of Transportation has released new guidance for parents who are flying with their children on airplanes—without paying extra fees.

The U.S. Department of Transportation (DOT) issued a notice to airlines on Friday to seat young children who are 13 or younger next to a parent at no extra charge, according to a new statement from the DOT. The department said its Office of Aviation Consumer Protection (OACP) will review airline policies and consumer complaints later this year.

“Although the Department receives a low number of complaints from consumers about family seating, there continue to be complaints of instances where young children, including a child as young as 11 months, are not seated next to an accompanying adult,” the DOT wrote in the notice. “If airlines’ seating policies and practices are barriers to a child sitting next to an adult family member or other accompanying adult family member, the Department will consider additional action consistent with its authorities.”

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Airlines are being called on to do “everything that they can to ensure the ability of a young child (age 13 or younger) to be seated next to an accompanying adult (over age 13) family member or other accompanying adult, without charging fees for adjacent seating.”

In four months, the OACP will monitor the airlines’ compliance with these new guidelines, and enact further regulations if necessary.

As with most things, there are a few catches: airlines need to seat young kids next to an accompanying adult, but they’re not required to seat an entire family together. The new guidance also doesn’t require any airlines to upgrade anyone’s seat “to another cabin class or a seat with extra legroom or seat pitch for which additional payment is normally required.”

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For now, the DOT advises parents and families to purchase tickets from airlines that allow you to select your assigned seats (like Delta, American, or United), or book flights where all members of your family can be on the same reservation.

If you’re experiencing a seating issue prior to your flight, the DOT recommends contacting your airline directly prior to departure.