Also, I think there are certain advantages to not being the 'favoured one'.
Sure there are. I went to a top notch private boarding school and had the best education available, I spent a lot of holidays with friends and extended family during my secondary school years, and on the rare occasions I was at my parents' house I had no curfew as long as my chores were done. I was free!
OTOH; when one of my brothers thought it would be funny to hide cheese in my meal because he wanted to see the reaction I had, I went to hospital alone and spent 3 days in ICU without a single visit from my mother because the twins 'needed her more than I did' (my father was away and went ballistic when he found out). All the freedom in the world doesn't make up for the knowledge that your own mother doesn't care enough to make sure you're going to be okay, she didn't even punish the brother who doped my food because 'it was just a prank'!