My son applied to Harvard and got accepted. I'm going to throw away his acceptance letter before he gets the chance to read it.
You're not happy for him? Why would you ruin something like that for him?
If he's going to Harvard, he doesn't need my support.
You seem angry about his acceptance. You're his parent, so your support is very likely important to your son.
Well, like I said, if he's going to Harvard, my support is unnecessary.
I don't understand why you're thinking this way, but it's wrong of you to throw away his acceptance letter.