I was a single child until I turned 8.
At first I wanted a younger sibling very much, but after that I realized I'd rather be a single child.

So yes at first I did bother that they pamper and favor my younger brother more than me.

But now I'm like who cares, I got two feet and two hands, I can work for myself, I can earn my own money. I can live on my own. So they can pamper my younger brother all they want as long as I get the benefits of being treated as their child.

Bottom line is, I used to care but I don't really care anymore.