Admittedly I only have one child thus far (not for lack of trying!) but I LOVE taking our son abroad. We went train hopping around Emilia Romagna when he was 18 months, visited Granada and Nerja when he was 22 months and are now going to Sicily in June when he will be 2.5 :D
I think the key to success is planning accordingly. Things we did that helped:
1: We made sure we had a spare change of clothes, snacks, small quiet toys, baby headphones and a iPad for the plane.
2: We showed our son videos of airports and planes for a few weeks beforehand (and also played airport pretending to go through security etc) so he was at least a little familiar with what would happen.
3: We bought a good travel buggy. We have the Ickle Bubba Globe which is cabin sized, lies flat and is half the price of a Babyzen Yoyo. We also got a SnoozeShade to go over it for naps on the go.
4: Show up to the airport early so you're not queuing for as long to get through check in. I'd also recommend keeping passports and tickets etc in a zipped wallet so it's easy to access.
5: Travel light and book an apartment rather than a hotel. With access to a washing machine, a balcony and good weather, we could do eight days with one carry on sized suitcase (for son and his reusable nappies) and one medium sized suitcase for husband and I. An apartment also gives you a space to relax alone after you've put the kids to bed. We've done a mixture of both in the past and stayed in an apart-hotel but decided apartments were more convenient (and cheaper!) with a toddler ultimately.
6: Have a good changing bag! I have the Cath Kidston Smart nappy bag (bought it on FB Marketplace unused for really cheap) which we used to take on our travel days out and about in the UK as well as abroad. Son has now potty trained and I'm kinda sad I won't be bringing it this time 😂 The best part about it was that it had a smaller bag inside that you could remove and that fit perfectly in the basket of a travel buggy. Inside I could fit a set of toddler cutlery, bibs, four terry nappies with a spare change of clothes, bum cream, cloth wipes and spare nappy wraps... basically everything I'd need for a day out in one tiny bag.
7: We got a fold up travel booster seat for restaurants so we didn't have to worry about there being a highchair. We went with a foam style one rather than a rigid one. This also fit, with the changing bag, neatly under the buggy.
8: Research restaurants in the area you're staying beforehand. I have an Excel sheet filled with restaurants that I know everyone will be able to eat at (after viewing their menus online and checking their trip advisor rating). It sounds extreme but when you're tired after a long day exploring it makes it so much easier to just pick a place off a list, whack the directions into Google and walk there knowing you'll get a good meal and don't need to waste any precious time waiting around.
Sorry for the waffle but I hope some of this info helped! :D Happy to answer any more questions you have.