Phone Bill

So this is something that happened to me and it really sucked so I figured I'd put it on here. The other night my dad came storming down the stairs yelling at my little brother and I about how we had cost him over 900 dollars in phone bills. Of course my reaction was WTF! Because he had told us in the past that we had unlimited talking locally and texting. I obviouslly took advantage of this freedom. But he had made a stupid friggen mistake and because of it he wound up paying a lot of money for something he would rather not have. The worste part is though that he tried to blame me for it. Informing me that I had misused my rights on the phone and that it was all my fault that he had to pay. Now I feel like it's his own stupid fault and I should not be blamed for his stupidity. What do you think?