After reading the Dogs biting thread I thought I would add something.
A few weeks ago I had finished walking my dog in Ashridge forest and was enjoying coffee and cake with my wife and pooch (pooch had some dog treats, not coffee.) A chap came strolling over with his small son and without asking if it was ok to stroke my dog the boy pats her on the head as if he was trying to flatten it, then attempted to poke her in the face with a stick.
Luckily my dog is very gentle and passive, but my wife isn't. We don't have any children yet, when we do they will be encouraged to feel comfortable with animals, but poking a big dog in the face with a stick is going to get a reaction, my wife was furious!