We're in it together, through thick and thin.
我們同甘共苦，患難與共。
We're family.
我們是一家人。
No matter what your problem is, we are together through thick and thin. We're family.
不過你有什么困難，我們同甘共苦，患難與共。我們是一家人。

No matter what.
不管怎樣；無論如何
It implies that no matter what happens, the family is still together with one another.
這意味著無論發(fā)生什么事，一家人始終會團(tuán)結(jié)一致。

I've got your back.
我支持你。
Buddy, I know you're short of money； I've got your back. How much do you need?
兄弟，我知道你缺錢。我會支援你的。你需要多少？

It's going to be okay.
會沒事的。
Don't worry about your presentation today, it's going to be okay.
別擔(dān)心今天的演講，會順利的。

It will come out in the wash.
事情最終會水落石出；事情最終會過去的
Don't worry about that small issue, friend. It will come out in the wash.
朋友，別擔(dān)心那件小事。事情最終會水落石出的。