This little episode is a reminder of how we always have a choice in how we react.  I reacted well in my opinion in this situation but i don’t always do that.  Simply remembering that I CAN react this way is going to help you and feel GOOD. = Happiness. 
The two books by Ajahn Brahm i mentioned here are these:
Who ordered a truckload of dung? and 

Don’t Worry, Be Grumpy: Inspiring Stories for Making the Most of Each Moment

Enjoy these books! great for bigger kids too. 

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