Flying with young kids is rarely easy, no matter how often you do it. It gets better as they get older, of course, but until then it’s usually a slog.

Who wants to stay home, though? Not many say recent reports, especially U.S. millennials, who are traveling with their kids in record numbers and spending more time vacationing than any other American generation.

Although millennials are more travel savvy than previous generations, as is Gen X, it doesn’t always mean smooth sailing when kids are involved. What really matters is the ability to plan and prepare.

“This is absolutely essential,” says Liz Portalla, a Massachusetts-based sales rep who logs more than 50,000 air travel miles per year. “With kids, you definitely can’t wing it.”

Although Portalla travels mostly for business, she’s also flown often with her three kids, and has had her share of glitches. “Even when everything goes smoothly, traveling with young children can be very difficult,” she said. “So be prepared. Create a detailed itinerary and give it to your family, get TSA Pre-Check or Global Entry to ease the security process, make a list for each family member, and pack well in advance.”

Other strategies Portalla recommends, as do other parents, include traveling at the right time, sitting in the right spot, and packing the right stuff.

The best time to fly with kids

While you can’t always fly at the optimal time (based on your child’s age, that is), it’s great when you can. The best times, most agree, are between three and nine months, when kids aren't yet mobile, and any time after age two or three. The idea here is to bypass the toddler phase, and, more importantly, to avoid flying with young infants.

The latter is especially risky says Dr. Mark Waltzman, assistant professor in pediatrics at Harvard Medical School and pediatric emergency room physician at Boston Children’s Hospital.

“Unless it’s an emergency I would wait until a baby has had its first set of immunizations, so they should be at least two months,” he said. “The reason is that the air in airplanes is recirculated in a confined space, so there’s a greater chance of contracting an illness when flying. A newborn’s immune system isn’t as robust, and if they catch a cold or get a fever it could be much more serious.”

Illness can also impact the timing of a trip for older kids. If a child has a fever and/or an active ear or sinus infection, parents should think twice about flying and consult their physicians Waltzman said. “Ear and sinus infections can be very uncomfortable, and would make them miserable during a flight. With an ear infection, there’s also the risk of a ruptured eardrum.”

Selecting a carrier and flight

While price is always important, other factors might outweigh this, like access to changing tables. Not all aircraft and airlines have them, so if you think you’ll need one, check before booking.

The same goes for bassinets. Many airlines offer these, even for U.S. domestic flights, but not for all aircraft. In some cases they’re only available at the gate, on a first-come, first-serve basis, while in others they can be reserved ahead of time. There can also be restrictions on where the bassinets may be used (not in business class, for example).

Seating

Here’s another area where you’ll want to weigh your options. Do you go for the bulkhead seats so you’ll have more room (especially if you’re with a toddler) or sit in the back, closer to the bathrooms and flight crew? If you opt for the bulkhead, you’ll need to book as early as possible, since these get snapped up quickly. For seats near the back, booking is usually much easier.

The most important thing, though, is being able to sit together. If this doesn’t look doable when booking, call the airline and ask if it can be arranged. Then, once you’re all set, check your seat status again as soon as you get to the airport.

You can also ask for help with this at the airport. “Just ask a gate agent or flight attendant if they can assist,” says Taylor Garland, spokesperson for the Association of Flight Attendants-CWA. “Most airlines will try to accommodate this as much as possible; in fact they usually require that children under a certain age sit with a parent, or other adult in the party.”

What to pack when flying with kids

This one can be tough, although it basically comes down to carrying on whatever you and your child will need for the first 24 hours and checking the rest. This ensures that you have what you need during the flight, and immediately afterward if your luggage is lost. Also, when it comes to food, diapers, and wipes, always pack more than you think you’ll need.

The basics for infants and young children include the following:

IDs: a passport for international travel, even for newborns, and passport or birth certificate for domestic flights (not all airlines require the latter, but bring something just in case)

Diapers and baby wipes

Bottles and formula, juices, etc.

Baby food and snacks

Security items – pacifiers, blankies, loveys, etc.

Medications

Sippy cups

Disposable changing pads

Paper towels

Blankets

Change of clothes – for both you and your child

Small, quiet toys, including some your child hasn’t seen before

Antibacterial wipes – for disinfecting germ-laden tray tables and other items

Phone charger and extra battery pack

Headphones and iPad or other device for older kids, with kids’ programs and apps

Baby carrier, wrap, or sling – if you don’t have a car seat, wearing your baby on the plane is the next best thing Waltzman says; this will keep him or her safer, especially if there’s turbulence

Car seat: provides an extra level of protection and is often more comfortable for your child; you’ll then also have it at your destination.

Steps to take before and during the flight

Make lists: To be sure you don’t forget anything important, which isn’t uncommon when traveling with kids, make a checklist of pre-departure to-dos (turning down the heat, watering plants, and taking out garbage, etc.), and a checklist of what to pack.

To be sure you don’t forget anything important, which isn’t uncommon when traveling with kids, make a checklist of pre-departure to-dos (turning down the heat, watering plants, and taking out garbage, etc.), and a checklist of what to pack. Consider backups: Make paper backups of all important docs and store these apart from the originals, in case you lose a bag. These include passports, birth certificates, your drivers’ license, etc. Also print a backup of your boarding passes.

Make paper backups of all important docs and store these apart from the originals, in case you lose a bag. These include passports, birth certificates, your drivers’ license, etc. Also print a backup of your boarding passes. Check your status: Check your flight status before you leave home, especially if the weather’s bad, but even if it’s not (as you never know where your plane is coming from). Also check in before you get to the airport and plan to arrive early.

Check your flight status before you leave home, especially if the weather’s bad, but even if it’s not (as you never know where your plane is coming from). Also check in before you get to the airport and plan to arrive early. Dress in layers: This lets you add and subtract as needed, which is helpful when traveling between hot and cold locations.

This lets you add and subtract as needed, which is helpful when traveling between hot and cold locations. Prepare older kids: Explain what will happen and the basics of in-flight etiquette (that is, no whining or kicking seats). Consider bribes for good behavior.

Explain what will happen and the basics of in-flight etiquette (that is, no whining or kicking seats). Consider bribes for good behavior. Use curbside check in: This can simplify things considerably if it’s available.

This can simplify things considerably if it’s available. Familiarize yourself with TSA regs for liquids: If you plan to carry on formula, breast milk and/or juice for babies or toddlers (which TSA allows in “reasonable” quantities), be sure to declare it at the beginning of the screening process. You must then remove it from your carry-on bag to be screened separately.

If you plan to carry on formula, breast milk and/or juice for babies or toddlers (which TSA allows in “reasonable” quantities), be sure to declare it at the beginning of the screening process. You must then remove it from your carry-on bag to be screened separately. Befriend the gate agent: If you run into problems once you’ve cleared security, your gate agent is your go-to for help. He or she can often resolve many issues.

If you run into problems once you’ve cleared security, your gate agent is your go-to for help. He or she can often resolve many issues. Head for the bathroom: Make a pit stop right before you board.

Make a pit stop right before you board. Board first, or last: If you’re traveling alone with a small child who’s mobile, boarding first is probably easier. But if you’re with another adult, he or she can board first with the bags, and you can board last. This gives your child extra time to run around.

If you’re traveling alone with a small child who’s mobile, boarding first is probably easier. But if you’re with another adult, he or she can board first with the bags, and you can board last. This gives your child extra time to run around. Minimize ear pain: Nurse or bottle feed an infant during takeoff and landing, or provide a pacifier. Older kids can swallow or yawn (which can make for an interesting game). When feeding your baby, know that timing is key. For takeoff, wait until the plane is ready to clear the ground. When landing, start sooner rather than later, as the descent can take much longer.

Nurse or bottle feed an infant during takeoff and landing, or provide a pacifier. Older kids can swallow or yawn (which can make for an interesting game). When feeding your baby, know that timing is key. For takeoff, wait until the plane is ready to clear the ground. When landing, start sooner rather than later, as the descent can take much longer. Hand out diversions as needed: Never give your child everything all at once, but wait until he or she gets restless. Only then is it time for the next toy or snack.

Sit back and relax: Just kidding! Unless your child naps, this isn’t likely, but at least you won’t be bored.

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