] ] So at least the "first son" status didn't ruin his character for him.

] What about the bit in S&S (chapter 49) where Edward talks about the idleness between age 18 and 19 caused by being a first son with no employment? He himself attributes his fancying himself in love with Lucy because his mother did not choose or allow him to choose any employment.

I still don't think it turned him into a bad person -- not like Willoughby, for example. And, I'm not certain that a second son would necessarily have had more to occupy his time at that age if the family had money. Robert Ferrars was equally idle, and vain as well, and he was the second son. :-)