Why is my 2 yr old so mean??

My son is 2 yrs old (3 in Nov). He is very mean to everybody. He will just walk up to my husband or I or his sisters (11 and 7) and just hits them. He also does this to his cousins. The other night his sister (7) was sleeping and he started gouging her while she was sleeping. He also hit her in the head w/ one of his metal planes one day she was sleeping on the couch. He pinches, gouges, punches and kicks for absolutely no reason. He is also mean to the animals. He tries to hurt people for no reason at all.  Is this normal behavior?? What can I do to help him not be so mean??

[Kimmi1565]

That is not normal behavior.  I have a couple questions for you..

1. Have you brought this up to the doctor?  
2. What do you do when he does this?
3. Is there a lot of yelling in your house?
4. Have you talked to him about his behavior?

[AnnieBrooke]

My son clunks me on the head when I am sleeping, because he wants my attention.  So to the above list, I'd add, is he getting the attention he wants, or is he getting attention only when he acts out?

[mammo]

I hope he is being disciplined when he does this, so that he learns there are consequences for his bad behavior.  Get down to his level and calmly but sternly tell him."we do not hit other people" and put him in time-out for 2 minutes.  Then when his time-out is up, tell him this again, and give him a big hug and tell him you love him.