Why do our eyes water when we are tired?

Question

Why do our eyes water when we are tired?

Answer 1

I think it is becuase we are in need of sleep to rejuvinate our whole body and we need to et extra oxygen to our eyes and when we yawn or squint to make up for being tired our eyes water as a result and we then get oxygen to our eyes and then the whole process starts over again. It is just one of those things.