I have a problem. Why is the beginning of my outline so different from how it turned out towards the end?

Perhaps, I have too much fun with fun and games... (Rising Action). I spent an eternity on that one.

Stewart, my protagonist, was supposed to get blamed and hated by the society for starting the sibling swap (helping other kids too)... that was at least what I wrote in the beginning.

By the time I reach Rising Action... suddenly, Stewart is perceived to be the good guy... but William, the supporting character, shines even more because he is the one who is pushing to do the good stuff while Stewart wants to stop his business all the time... like... in Stewart's words: "This is not what I planned it to be. Why am I serving kids I hate?"

And by mid-point.... they both become heroes....

Then, I look back at the beginning and realise that this is NOT supposed to happen...

Wait... whaaat?

Is this normal?

So, my beginning of the outline does not meet towards the end of the prep... it is in fact diverting... from what I thought was a good climax... now the climax and the lesson is blurred and not delivered. At least I have not sketched that one in detail yet...