It sounds sort of obvious when you think about it but did you ever think. Being born first, second, third,.. or an only one. I really think it makes a fundamental difference. It is training and orientation at the basement level.
Now personally I think being eldest is better, but as is often thrown at me for other reasons. “Well you would wouldn’t you”.
I think I would need to do a dissertation to half cover this but here is “the hop on and off open top city tour” version. It is way more complicated than this but…
A child is born and starts to grow. Firsts and onlys start the same way. There is nothing between them and their parents. They get attention, but their parents are starting out too, wondering what happened to the manual. They learn to interact directly with authority not really questioning that and if they develop right they question and negotiate. They take authority but are not cowed by it, they push to be allowed to stay up later, get more allowance. Trailblaze.
They learn to be ok on their own, self sufficient and reliant.
Now when a little brother or sister comes along the firsts and the onlys diverge.
Firsts get to learn responsibility, new social skills, and so much more. They also get to understand they aren’t exclusively important. They learn fairness and sharing and to administer it. How to get on with others. They learn how to teach and leadership. Teamwork.
Meanwhile onlies get to become more self sufficient and as they get older how to make new friends in the wider world.
Second borns don’t have just two parents, but an older sibling, playmate and expert on everything they want to know about, team management, back up, but also competition for what TV show to watch or day trip to go on. Negotiation. Teamwork. Second borns get social skills, how to entertain and have to up their game because they
interact with someone more experienced and mature. They also get the benefits of their older sibling’s trailblazing by default.
Third borns have a different experience in turn, They are one of many from the start, but get looked after by the first two. They change what the first two experience, with the second starting to learn skills the first has developed.
So depending on what order you are borne you get whole different viewpoints, sets of skills and ways of reacting to most anything. Isn’t the world interesting?