You need to be happy always because you don't know who is watching you. Why not be cheerful, put up a smile, and be happy with the things you do? Life is not a bed of roses. You will always face challenges in life. What then do you do when you encounter problems? Remain like that forever, and become sorrowful? No, you have to put the troubles aside, while you put on that smile. I want to reach hearts, I hope this was helpful to you? Have a nice day!