Cabin pressure - Children
It helps to breastfeed or bottle-feed babies when the plane is taking off and landing. Your toddler will also find a drink, such as a fruit drink box, will help. The swallowing motion can help reduce the build-up of pressure in their ears, which is quite painful for babies and children. Giving a dummy may also help as may chewing sweets or dried fruit for older children.
Dry cabin air
The dry air in an airline cabin is dehydrating and can irritate nasal passages. Consider asking "your pharmacist for a 'buffered isotonic saline' nasal spray for infants, which reduces discomfort and reduces chance of picking up bugs. This is just a thought.