First, if you can afford to have your daughter in her own seat, rather than a "lap child", it's safer - but you have to bring the car seat, and it has to go in a window seat on the plane. I use a "Sit 'n Stroll" from Triple Play Products; I can roll it through the airport and convert it back to a car seat on the plane. Warning, it won't fit through airplane aisles anymore (unless you're stopping in the first class section ;)). At 18 months, my toddler had her own (smaller) rolling backpack (she wouldn't have been able to wear it, but it gave me a strap to add to my load if necessary; it wasn't necessary with her, she rolled it around like mommy, lol.) Her backpack had many of her favorite treats and new books, a magic board (you lift up the top film and the writing disappears), some quiet toys (activity doll, play camera, crayons & coloring book, etc.) and her purse (mirror, brush, play cell phone.) If your toddler is less independent, a harness is a good idea in the airport; there are so many distractions! My girl had some ear problems, so her doctor recommended a teaspoonful of Pseudopenephrine (?sp) one hour before take off. This means it will be one of the liquid items that have to pass the 3-3-1 rule, and fit into your one quart baggie. Allow yourselves at least two hours at the airport, and probably a third if you're traveling in the next few weeks. After you pass through security, buy some bottled water, fresh fruit, and her favorite juice - bring her empty sippy cup in your carry-on. Yes, the flight attendants will eventually be offering liquid refreshments, but you want to make sure she is swallowing during take offs and landings. She's too young for the chewing gum trick, but you may consider lollipops (my doctor okayed them at 15 months for travel, but my daughter didn't want them then.) If you have to change planes, allow at least an hour layover, two if you're going to sit down to eat. Put her in night-time diapers or pull-ups (whichever she is wearing, you want the extra absorbancy) and change her every two hours. Double (the number of pull-ups) that you think you'll need in your carryon, and include plenty of wipes, diaper sacks, and a couple of clothing changes. Layer her clothes, so you don't have to pull everything off for her to be comfie. Whatever you don't anticipate needing during travel, pack into checked baggage; you will have to bring enough along as it is, so, even if you have to pay to check your bags, it's worth it. And, above all, don't stress yourself out. If she cries, that is actually good for her ears, and most of your fellow travelers will understand (some may even offer to help entertain.) Make sure you have whatever you need for yourself, take care of yourself first (you can't do anything for her if you're not well) and relax as much as possible. Good luck!