Some Thing in my Family that I didn't know

When I was 12 years old, I looked over my family pictures and then their old stuff. I found an adopting letter in my Dad's, I was surprised and thinking "Daddy adopted me?" I looked at it again and I saw my Dad's name on the one who was adopted and my Grandparents on the adopter name and shouted in my head,"DADDY WAS ADOPTED" (O.o) I was frighted with the news I asked dad and he said it is true. But I can't believe it, my dad looked so much like my Grandpa but he was adopted!! (_ _ll)