I have one older sister. An advantage would be that my parents let me do things at an earlier age than they did my sister. I got my ears pierced younger and got to watch more mature movies than she did when she was my age. A disadvantage is that she was really bossy so I had to deal with that.

I'm the youngest

There's no advantage

I have a sister and one brother still alive and have passed away

I am the youngest and have an older half-sibling who I was raised with for a time.  We both had the same mother and different fathers.  My mother divorced my father.  My mother chose her eldest daughter as her favorite so I ended up being  Cinderella and was not treated equally.  And that's the short story. Families can be cruel. I would think that would apply to any culture.

Doesn't being the middle child of three mean that you're the smartest? My sisters might not agree, but hey. What can I say?