First, the touch the baby and the parents abandon it is a myth. I have had personal experience to prove it. Second, the bird may have been defending its territory. Have your dad take you and the baby to the vet. They will know what to do. Hurry! Don't let it die!

I'm at my older sisters house. I was packing up getting ready to leave, I had got my stiff into the car. I look by her tree and see a baby finch learning to fly. My dad told me it's fine and just leave it alone. So I did. I go inside and am sitting in Candis' rocking chair then I hear a werkrd noise. I look outside and see this blue bird ripping this baby to prices. I yelled for my dad. He ran outside and chased the Blue jay away. I was scared and looked at the baby. Blood was everywhere. I decided to calm Down a bit. I wanted to hold the bird but my dad told me if I did the parents would abandon the baby. So my question is, WHY on earth would a Blue jay attack a baby finch?