Do get your daughter her own seat. I have spoken to other parents that didn't get seats for their kids on overseas flights and they regretted it. Book your flight early. Once a plane is 60% booked, prices go up for the remaining tix. If you can, book a DIRECT flight to your destination or close to your destination. If you are going to Europe to see friends and family, find someone who wouldn't mind driving a little longer to pick you up. NOT having to change planes with your daughter is definitely worth it. Get one of the latest flights in the day. Talk to your pediatrician and ask if it's okay to give your daughter children's benadryl when you get on the plane or right after take-off. It will get her a little drowsy and hopefully help her to fall asleep. Go to the dollar store and buy toys that you know your daughter will like. New toys will capture her attention longer than old toys but do bring a favorite stuffed animal or blankie for comfort. (Make sure you can somehow attach the animal or blankie to you or the diaper bag. You don't want to loose her favorite "luvy" during travel). Be prepared to walk around with her during the flight, so bring comfi shoes for you and her. If you can, bring your own (travel) DVD player and some DVDs for her or borrow a DVD player from one of your friends. If you don't have a carrier or sling for her that she still fits in, get one. I would recommend the Peanut Shell sling (you can order it on-line. Get the cotton/spandex combination). I use one for my 17 months old son and he loves it. When things are new to him, he wants me to carry him and this sling still allows me to be hands-free while he is securely tied to me. Best of all, it fits in his diaper bag. Also, most European countries require toddlers to be in a car seat when traveling in a car (when you get there). Instead of lugging one with you, go to an E-Bay site that is in the country of your destination and get one through E-Bay (same goes for other big items, you may need over there like a pack'n play for her to sleep in). Have it shipped to wherever you will stay. Or if you are visiting friends and family, see if you can borrow one from someone. I don't know what type of stroller you have, but don't bring your full-size stroller if you don't have to. Bring a smaller size, in case you have to carry it up and down stairs. I don't know where you are going in Europe. I am from Germany and there are still public places in Germany that only have stairs. No elevators and no escalators. (I went to Munich once and the way I had to go through the airport from the bus station, had only stairs). There are strollers you can get that are slightly bigger than umbrella strollers and very lightweight. While traveling, make sure that the diaper bag you bring, is very comfi and easy to transport. Sometimes, you will have to just carry it for a long time. A backpack is great to travel. If you get just a regular size backpack (not a diaperbag backpack), you can fit more stuff in it b/c the regular size ones are a little bigger than the diaper backpack. Be smart with packing stuff. Don't overpack. Think about what you can buy at an airport or in a store, should you run out of one item. And don't forget to pack an extra outfit for you on your carry-on. Some kids get airsick and throw up. You don't want to travel in cloths that smell. I would also pack trial size "spot removers". You can get them in little packets. They are great for removing spots from cloths. Good luck on traveling with your little one.