I scrambled the jigsaw puzzle that my grandfather and brother were assiduously working on for the past few months
They worked so hard on it. Why would you scramble it up for them?
Obviously it's my fault, I was always the scapegoat since I was born
Well in this case I think that they are right to be upset. You should not mess with someone's work. It is not very nice.
Well I was bored.
If you wanted their attention, why didn't you try and ask joining to build the puzzle? It would be a great activity for you all and would help you get away from that scapegoat image, instead of actually reinforcing it by ruining their things.