I saw the shirt in person, it is INAPPROPRIATE. The anatomy of the dogs rear, looks worse than it does in the picture posted on here. And he was given a choice to just turn it inside out. But he chose to call his mother (obviously because he has been taught no respect) and she is blowing it out of proportion.
So says you. You can be offended at what ever you like.
..as pointed out upthread, what 12 y.o. hasnt seen a dogs butt?
I hope she pulls her kids out and home schools them. They will learn so much more and be head and shoulders above their peer group by graduation. Guaranteed.