Stubborn Confusions

Anyone who's been reading this blog for a decent amount of time and thinks I am not a member of a group called Spelling and Grammar Nazis is a nitwit. I'm not even apologizing for my seeming lack of manners, I am so mad. I discovered there are still some things I am confused about, and I am actually thinking of announcing a reward for the person who clears my doubts (though whether it will be a used pair of slippers or my old, out of order keyboard remains to be decided).

First: Why is it Mother's Day and Teacher's Day and Father's Day? These are days for all mothers and all teachers and all fathers; shouldn't the apostrophe be after the 's'? Or not? Why not? (I'm pretty sure I have you stumped there)

Second: Is 'okay' an adverb? Or rather, can it be used as an adverb? "Did you get home okay?"--isn't there something terribly, terribly wrong that jars like a note out of tune? Or not? Maybe not. Then again, maybe.

Third: Why don't we get rid of the rule about split infinitives? Word's style check makes some of my sentences look awkward. Split infinitives are fine. Language evolves. Not that we should add LOL to the dictionary, though. Most people don't even bother to capitalise that.

That's all that's bothering me right now. I will remember something I have forgotten soon enough, (hey, what an ambiguous sentence; remember soon enough or forgotten soon enough?) and I will have to create a new post. Dash it.