Think it's stressful traveling with your children? Don't chew your nails to bits just yet. There may come a day when you have to send Junior off into the wild blue yonder all by himself. What's to know before sending your sweet mannered minor into the skies? Here's the lowdown:

• Paperwork and Identification: Most airlines request proof of age for your child, as well as your own ID. Expect a marathon of forms to be filled at check-in, which ask for the name, address, and phone number of the adult picking up your child upon landing. Some airlines, like United Airlines, will want this information even before you arrive at the airport so do call ahead.

• Age Restrictions: All US airlines agree that all unaccompanied minors must be over 5 years old. The upper limit, though, is different depending on the airline. Some airlines—like AirTran, Spirit, and United Airlines—will allow children to travel alone at 12 years old. Others, like Delta, American, Northwest, and Frontier agree that 15 is a more appropriate age.

• Children Under Five: Even though these children can’t travel alone, some airlines allow them to travel with a young sibling. For example, Frontier Airlines will allow a child less than five years old to travel as long as he/she is with someone over 15 years old.

• Fees: Sending away the kiddies unaccompanied comes with a fee. unless you’re flying with Southwest Airlines. JetBlue, AirTran, and Alaska Airlines charge less, at $25-$30 each way, while United Airlines charges $99 each way. On average, most airlines will charge about $40-$60 each way.

• Escorting your child: Airlines expect the adult at the departure airport to accompany the child to the gate, and wait until the plane has left. You can pick up an escort pass to ease through security at the time of check-in. The adult at the destination airport will often be granted access to the gate terminals to meet the child as he or she exits the plane. Otherwise, an attendant will escort the child to the designated arrival area. The adult receiving the child should be at the airport 20 minutes prior to the arrival time, and have proper identification.

• International Flights: Rules, fees, age restrictions, and necessary documentation are different for change for international flights. Double-check the requirements before sending an unaccompanied minor abroad.

• Optional Assistance: If you think that your 12 or 15 year old still shouldn’t be traveling all alone, then you can request assistance for your unaccompanied minor. This service is usually available for children up to 17 years old.

• Connecting vs. Non-stop: Some airlines, like Frontier, JetBlue, and Southwest will not allow your child to travel alone on connecting flights. Most others will allow children to fly on connecting flights if they are 8 or more years old. However, you’ll be charged extra for that connection. For example, Continental charges $50 for a direct flight and $95 for a connecting flight.

• Red-eye Flights: Most airlines don’t allow unaccompanied minors on red-eye flights or on the last flight of the day. These restrictions can vary, depending on the destination and flight length.

• The More the Merrier: It’s customary for airlines to charge the unaccompanied minor fee only once, when two or more minors travel together.