In Swedish, kids (at least a few decades ago, when I was a kid) sarcastically say:
Kul för dig!
This literally means:
Fun for you!
Or, more clearly:
That's good... for you!! (But what's it to me?!)
Oh yeah? How... fun... for you. I'm so... happy... for you... and I'm not jealous at all.
In English, there's a very common phrase:
Good for you!
Good on you!
Maybe it's just because I think of the Swedish phrase, but whenever an American says this, it always comes off as sarcasm to me. As if they really aren't saying that something is "good", but rather that:
I guess that's good for you[, you boastful little]...
But maybe in English, it's genuinely a way to express that you are happy for somebody else and their success, or whatever was said prior?