If you have experienced it, is it really a 'thing'? Doesn't being the eldest and the youngest also come with some form of change, responsibility, differences in dynamic?
If you/your child were the middle child how has it impacted you/your child?
I am one of 6 children, we're all close but all very different. I would say my eldest sister was neglected because of the rest of us coming along, but she is the eldest, not the middle child..