My DGD reads aloud to me twice a week. She is 6 and a good reader. I have just bought 'Horrid Henry's Underpants' for her, but on looking through it, I see there are mentions of 'de-bagging,' i.e. pulling trousers down. I am not sure that this is appropriate material for a 6 year old girl. Should I just ditch the book and buy something else?