I've flown with my now 18 month old son twelve times since he was 3 months old. Everyone is giving great tips!
I fly alone with my son a lot. I usually babywear through security.
My suggestions would be:
-Consider booking seats a few rows behind the wings of the airplane. The noise helps lull babies to sleep sometimes and it muffles the sound of crying. One time my son cried for a few minutes and at the end of the flight the person in front of us turned around and said "There was a baby right there?! I didn't hear a thing!"
-Bring lots of snacks and at least one change of clothes.
(You can bring formula, breast milk, baby food jars/pouches, bottled water through security).
-Depending how active your children are, you may want to wait until everyone else has boarded the plane to get on. A lot of airlines let families board first but if you have assigned seats (versus open seating) it might be worth waiting. In my case, my son gets fussy if we are seated and not moving for awhile. When I traveled with him as a lap infant it was so much easier to let him run around or calm him down while everyone else boarded. I fly alone 90% of the time so it becomes an issue of being cramped up next to a stranger. I bought my son his own seat the last time we flew and we did the pre-boarding option and it worked wonderfully because he had a whole (window) seat to move around in.
-Take off and descending is when the ear popping issue comes into play. I learned the hard way that the descending pressure change happens sometimes 30mins before you actually start landing. So, I'd suggest being prepared with a bottle or nursing when you start to feel a change in pressure yourself. Or, now that my son is older, I have a lollipop ready to let him have a few licks of if he refuses to drink/nurse at that time.
-I've found having baby games and shows downloaded on my phone or tablet to be helpful. That way if my son gets bored or starts trying to throw his toys there is another way to keep him occupied.
I hope this was helpful. Try to not to stress, and have a wonderful trip!
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