Answer:
You can do this with your friends. You can do this with your nose. But don't do it with your friend's nose!
I am your mother's brother's only brother in law. Who am I?
You do this into someone's ear when you want to be discreet.
No sooner spoken than broken. What is it?
Passed from father to son and shared between brothers, its importance is unquestioned though it is used more by others.
If itβs information you seek, come and see me. If itβs pairs of letters you need, I have consecutively three. What am I?