Why?

Why is the sky blue? Why do I have to wear shoes? Why is there dirt on the ground? Why do I have to behave at school? Why must I pick up my toys? Why do I have to go to bed at night? Why are you getting frustrated with my asking why? Why Mom? WHY? Moooommm.... Why are you not answering me?

and repeat for 32 hours a day... (thankfully he sleeps about 12)

My question is this... WHEN will this phase be over???? I know he is a big sponge right now and is learning so much. I am trying so hard not to get frustrated... but I can not complete a thought with out being asked WHY! Why is that?