You absolutely want a seat for a nearly 2 year old in my opinion! sharing a row of 3 with a stranger in ET would be quite stressful. In CE then no issue.

If you've got a Yoyo buggy or similar it's handy to have ready for the other end considering the long delays at immigration at times at the moment.

Otherwise fully charged tablet with games and shows, lots of new little activities to bring out during the flight and loads of loads of food is how I've got through it. It's pretty much the worst age if it's any consolation, flying with even a 3yr old is a lot easier. But just relax and don't worry about anyone else and they'll enjoy it too.

I remember lots of bad behaviour by rude or drunken adults but I don't remember any 2 year olds 😆