We all want to be in control. For the most rational way that provides better results is not to play hardball or vomit emotions haphazardly. When you understand that he who says what he wants hears what he doesn't want, your words and actions become more intelligent.
Imagine a huge rock, stable on the edge of a cliff. The rock is our emotional. While it is there, still, it gives us the impression that its stability is perennial. However, its position is likely to roll downhill.

Just a small touch, perhaps with the tip of your index finger, to make it lose its apparent stability and descend destroying everything. So is our emotional. One moment you are happy and cheerful; the next moment - by any eventuality - you become furious or saddened.
However, if the stone starts to oscillate, in the position in which it is, a finger on the other side is also enough to prevent it from falling. That's how our emotional works.
Just one finger is enough to prevent a disaster, if applied at the right time, before the triggering. Remember the story of Peter, the Dutch boy hero? He saw a crack in the dike and put his little finger to prevent the force of the water from increasing the hole and eventually breaking the dam. Just one finger, a child's finger, was enough to prevent a tragedy.
If you can detect a threat of emotional outburst just a moment before it breaks out, it will be very easy to avoid the tantrum, just put your finger in the gap in the dam.

Book: Change the world, start with yourself