The Truth Behind Our Tears!!

When does a smile become a frown? When do tears decide to flow gently down one's cheek? Is it normal to just simply want to cry for no apparent reason then just to let the tears flow? Do we really need to be sad in order to shed tears or can we also be so amazingly happy that we need to cry just because it's a special feeling of pure joy! It's enough I think to simply cry because it is a gift to do so! And with this gift do we tend to overlook it's properties? Think of this for a moment........ We cry at the birth of a baby, We cry at weddings even tho it's a celebration. We cry at a child's first day of school, and when they graduate from High School/College! These types of tears are welcomed emotions to shed our utmost of joy at a job well done! Yet more often than not these tears simply only flow when sadness occurs! Yet all this and more is simply a normal expression of emotion whether good or bad!!!! So again I ask, when is it not right for tears to flow? Is there even a right or wrong answer? I guess no one will ever really know!