This is an old good tick in case you may need one day to make peace between two fighting parts.
The trick is of a purely psychological nature, and thus can be widely applied (there are some other non-psychological more efficient tricks but they can be only applied by a person who can work with vibrations).
It is an old wisdom but it comes up very fresh even in modern times…
So basically if you have two people hating each other… just start telling each of them separately that the other one was just praising him/her for something (what can be realistic in that case). It is amusing to see the happy and astonished face of the person who hears that… :) It is important to start the procedure simultaneously, so that the both rivals can change their emotions at he same time.
Good luck in your peacemaker mission!
LOVE, axinia (image by me)