These are conversions between two friends:

A: I finally dated him .
B: really? What did you talked about?
A: everything!, but I told him about my getting involved with "MS", too.
B: Good, "that's the (very) right thing!"you shouldn't hide important matters from each other!

Another example:
A: I haven't been talking with him since last year.
B: but it was your fault, too!
A: yes, now that I have heard about him suffering from cancer,I want to compensate my past! I should go there and ask him to forgive me!
B: well, "that's the (very) right thing!",

I am looking for a phrase that means "that's the right thing you are expected to do/say" or " nothing else is expected, that's the right thing!",In those situations, actually I used a word by word Farsi translation in my examples, [ that's the (very) right thing] and I'm not sure if you use it or not! :)