I'm more inclined to see it as trained behavior because this kind of thing varies by culture. It's probably a combination of the culture and expectations aroun

I'm more inclined to see it as trained behavior because this kind of thing varies by culture. It's probably a combination of the culture and expectations around the individual rather than the individual themselves. Children are pretty often told they can be whoever they want to be by society, and so their bar is set pretty high. But when was the last time a 30 year received the message that they could be anybody they wanted to? People expect different things of older people, and the whole situation, with all of the narratives we use to define ourselves and others, is probably pretty self reinforcing. The attitude also likely shifts as you have a family and they grow up - again I think it's about what people expect. No studies to cite here, but just throwing out some ideas.