Frontier Airlines made things a little sweeter for families this week, announcing that kids can fly free. Most airlines have longstanding policies that allow “lap babies” to fly gratis, but Frontier is expanding that to any kid fourteen years and under.

But age isn’t the only restriction. As always, it’s important to read the fine print.

Most important, the benefit is available only to adults enrolled in Frontier’s “Discount Den” program, which itself costs $59.99 a year, and of course the kids have to be accompanied by a paying adult. But it’s not just that. The tickets also have to be booked online, the freebies don’t include any “extras” like baggage and seat charges, and only select flights on select dates qualify — specifically, 53 dates between February 1 and mid-August. The rules and qualifying dates are on the Frontier website.

All this raises the question: What else might be hidden in the veryverysmallprint of this new campaign? Here are just a few educated guesses:

And you thought the seats were already cramped.

Matthew Hurst at Flickr

1. Kids Must Fit Under the Seat in Front of You
Wait — you didn’t think Frontier was offering them an actual seat, right? That’s cute. People pay for that, you know. The under-the-seat area is actually pretty generous; as long as your kid is no larger than a medium-sized cat, a toy breed of dog or a large ferret, they’re good. And those mesh carriers are actually pretty comfy if you put a blanket and a little treat in there.

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So that's three bags...that's $575 total, including the $50 "overly whimsical pattern" surcharge for the bag on the bottom right.

Francisco Antunes at Flickr

2. Any Baggage for Kids Starts at $175 Per Bag, Per Flight Segment
Forget the first almost hundred years of airline travel, when bags were free. That was clearly an anomaly. Luggage is expensive to handle, especially when it’s a kids' bag with Spider-Man on it and whatnot. Also, for all free kids’ fares, no carry-ons or personal items are allowed. Frankly, you’re lucky you're not being charged for what’s in their pockets.

This has the potential to be very expensive.

Aaron Logan at Flickr

3. If Kids Make Any Noise, Not Only Is the Flight Not Free, the Fee Is Doubled
Look, there are paying customers on these flights, and they don’t want to hear the cartoon on that iPad, or the video game sound effects on that handheld. Yes, even buzzing through headphones. So here’s the deal: If anyone hears a peep out of a free-flying kid, the adult accompanying them has to pay twice as much as the original ticket price. Actually, Frontier should just institute this for the paying kids, too. Also people who bring hot sandwiches and stink everything up. Seriously, they’re the worst.

These are quite good, Billy. You may disembark when we reach Cleveland.

Li Tsin Soon at Flickr

4. Kids Must Provide Snacks for All Full-Price Flyers
Speaking of food, remember when Frontier used to offer free chocolate chip cookies? Well, the airline is bringing them back, only they have to be provided by the free-flight kids. None of that store-bought crap, either. However, fresh orange slices or cinnamon graham crackers will be accepted in lieu of true Toll House goodness.

Hey, kid — take this to 7C. My dogs are barking.

Public.Resource.Org at Flickr

5. Kids May Be Required to Serve as Personal Slaves of the Flight Attendants
Because in-flight service is a tough job, y’all. And really, flight attendants have had to put up with a lot from kids over the years — kicking seats, hitting the buttons because the lights are pretty, asking for drink after drink (back when they were free, too), and not actually finishing any of them and then spilling stuff and…well, is it any surprise that they might want to kick back, recline their seat very slightly, and make the kids bring them a drink or three?

Inviting.

brownpau at Flickr

6. Kids May Not Use the Lavatories
Despite the fact that kids may well be the only passengers who actually fit comfortably in the airplane lavatory, they are specifically banned from going in there. The reason is simple: because they just make a mess and don’t have the decency to wait to poop until they’re securely in the relative anonymity of the toilet stalls in the airport terminal bathrooms like paying adults do. Upper management is clear on the main reason that Frontier refuses to fly routes that last more than a few hours, and that reason is Number Two.

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Sure, a pronghorn is related to a goat...but it's just not the same.

Tomas Del Coro at Flickr

7. “Kids” Contractually Refers Specifically and Solely to Baby Goats
There’s a reason that Frontier’s announcement specifically doesn’t use the word “children.” (Besides, they need a baby goat for the tail of the planes in the new fleet.) Frontier: where “free” is a relative term.

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