The order you and your siblings were born in does make a difference to your personality and how you perceive yourself, according to YouGov polling.
The pollsters asked 1,782 adults with siblings about their personality traits. It found a clear difference: younger siblings are more likely to think they are funny, and older siblings are more likely to think they are responsible.
One thing that is important to note: part of this could be down to age rather than just family dynamics. As YouGov's Will Dahlgreen notes, older children are more likely to think they are successful compared to younger children but that could just be because their age means they have been in the workplace longer.