I believe this is the essay you were referring to:
I know I read an excellent essay somewhere (I thought it was the Lexicon, but I cannot find it) that goes into rather explicit details about the individual Weasley children and what their childhoods were mostly like. A big part of that essay was that Percy, being the "middle child", probably got kind of pushed aside, but I know it had information on Bill & Charlie as well. If anyone else finds it, can you post it?
I think that Percy looked up to Bill. He is the only other sibling to have been Prefect, Head Boy and to have gotten 12 OWLS. I think that when Percy was young he looked up to Bill's position as the oldest, and therefore the most responsible and most "grown-up" of the Weasley siblings. Being a bit pompous and ambitious, even at a young age, he probably admired how Bill handled leadership and how much trust adults placed in him.
Do you think Bill and Percy got along? How far do you think one could push their boundaries? For some reason, I see Bill as tolerant of Percy, but speaking once he got sick of the pompous attitude. Do you agree?