We willing be flying with my 16 month old baby for 12hrs need i worry about his ears or any other concerns can i give him calming drops or something.

Not particularly: The ear issue is only active during landing when pressure changes can stretch his ear drum. He can suck on something at that point & do fine. It is hard to travel with a 16 mo that gets bored easily and fusses anytime they feel like it. That's the same on a flight as it is at home, just hard because you have no ware to go. Invest in some things that will distract him.

Flying: A dose of Tylenol pre flight may help. Swallowing, chewing or warm wet face clothes along his jaw may help avoid ear pressure. Some movement and favourite toys may also help. All the best.

<2 yr flyer: Hard to get toddlers to swallow to equalize ear pressures on a plane, but otherwise no issues except keeping them occupied and calm. Maybe time departure with their usual bedtime for best results, also feeding them a meal just before takeoff may ease their tensions, although then potty issues arise !! Good luck, 12 hrs on a plane is a lot for a toddler