"Many years ago as a Relaxation Instructor I learnt that individuals are prone to mimic without knowing that they are engaged in this practice. Such knowledge was to prove extremely helpful in the years that followed as I engaged in working with many stressful, angry and out-of -control clients.
A good worker knows that to raise ones voice to an already angry and loud-voiced person is wholly counter-productive as it simply guarantees that they will become angrier. The only way is to talk in a firm yet softly spoken tone of voice. Similarly, mirroring the looks of a depressed person is only guaranteed to depress them further and simply telling them to 'cheer up' or 'snap out of it' when they obviously cannot is a futile request with which they are unable to comply.
The person in control knows that what how they speak, look, and act overall will be unconsciously mimicked by the other person who is not in control of their behaviour. Even the type and the pace of your breathing pattern will be copied unknowingly. Even a foetus inside the tummy of a pregnant mother is known to mirror the mother's mood and breathing pattern. When the pregnant woman is stressed, then so is her foetus, and when she is calm, so is her child inside.
There is little point to being in control of any situation if you do not try to exercise any influence as to the eventual outcome of others who are not in control. Now the only remaining question is who is copying who; the dog or the child or does it even matter?" William Forde: October 1st, 2013.