Why are kids so destructive?

Yeah, so... my daughter cannot seem to watch Finding Nemo without finding a way to destroy stuff. She's three years old, and she seems to take pride in making my personal belongings tattered, shredded and filled with what I can only describe as grafitti.

First incident is simple, she's in the computer room watching Nemo on my HDTV (from the 360). I go to give her a "sippy cup" and that's just not good enough, she wants a real cup. I humor her, she's three now, and give her a real cup ending the hand-off with "do NOT spill this, be very careful and keep it away from your brother" (he's only one and is equally destructive).
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"Daddy. I spilled."

FOUR SECONDS for my leather couch to be an above ground pool. No problem, I do a bit of yelling as a father has the right to do, and move on.

Then, tonight, I'm off at my german class and I get home... wife says the found all my PC dvd's and cd's and took them out of the case and started dragging them on boxes, the floor and whatever else might have abbraisive toppings. Ok, they got in trouble, and had to put them back. They're just computer cd's and backups of stuff, ok, I can live....

Then, she springs this one "Brianna was using your dry erase markers to draw on the leather couch." W.T.F? Let me tell you, they're only dry erase on boards... not LEATHER COUCHES.

So, luckily we bought the couch at a place called "Bob's discount furniture" with the "Bob's warrenty" which cost us extra money. But they have to come out for free and fix anything that isn't a wax burn or some other issue (hope its not "perminant marker").

Yeah, kids. Who knew?

CodeMonkey