If by worse, you mean that they develop a personality, then you're wrong. Babies and toddlers are experiencing everything for the very first time, so of course they are going to be uncertain about things and sure, they'll express this frustration about the fear of the unknown through being clingy, crying, and possibly screaming like a banshee. But they need to experience these things in order to learn and to find their feet. Hopefully, mum and dad will have a really good support system and a network of caring and considerate friends and family. But this also applies to strangers. So the next time you're sitting on a plane and you see mum struggling to get the kid to settle, instead of venting your irritation in the form of passive aggressive comments and loud tutting nosies, maybe you could, you know, help?