do you think birth order shapes one's personality?

I have to agree with this since at most cases, the order in which the child is born would influence how the child would develop. Depending on the situation of the family, perhaps the eldest might get more attended by the parents while not so much for those who would follow or it might be entirely different when it comes to the youngest. Most common notions would be that the eldest, since being first, is expected to be responsible while the youngest being dependent. It really depends on the environment where the person gets raised into too.

Definitely. I am the oldest of four and I am bossy and can intimidate the he11 out of someone. I'm also very responsible because I had to be responsible for my younger siblings while my parents were at work. My husband, on the other hand, is the middle child of three boys and he definitely has middle child syndrone. He was a problem child growing up, enlisted in the army during the Vietnam war, rode with a motorcycle gang because he was and still is reckless. His older brother is an over achiever which is why he's very wealthy and his baby brother is the nice guy everyone likes and looks out for. My baby sister is the same way. My middle sister is mean as he11 but that's how she's always gotten attention. My brother, second in the birth order and the only boy, was very bad as a kid but looked out for all three of us girls when he got older. Family dynamics definitely play a role in a person's development in my opinion.

I notice many brothers and sisters are alike in character .In one family, birth order sometimes can distingish them.First and third often alike and second and fourth are similar.No matter their appearances and their character,they are always the same.

Absolutely 100% YES! There is definitely a reason there are stereotypes for the oldest child, and the youngest child, and the middle child, and the only child! Of course, not everyone fits into these stereotypes. I do think birth order shapes a personality because of what you are exposed to. A first born child is often around adults. Sometimes they are around other children their own age. Some even are around children of other ages. But they arent constantly forced to interact with children of different ages. Children that have older siblings are constantly around their older siblings. Their siblings friends also come around. Children with younger siblings face the same situation with younger kids. I think these interactions that an idividual is prone to based on their birth order definitely gives them a different perspective on the world.