Now here's the thing holdingontometeeth; I don't happen to think it's funny or cute when a 5 year old bites someone. I think it's a behavioural problem that needs to be addressed, pronto. In fact, I wouldn't stand for a 2 year old biting another child, let a lone a 5 year who should have grown out of it by now. And it would appear that I'm not alone in thinking that way. Have a look at how young mum's feel about their children biting: www.mumsnet.com/Talk/behaviour_development/2371266-5-year-old-wont-stop-biting-at-school
Or this one, in which a a professional nursery deems biting, in a 17 month-old to be so unacceptable that he was excluded. Note, 17 months old. Not 5 years old.
www.mumsnet.com/Talk/nurseries/1607454-Nursery-excluding-a-17-month-old-for-biting-WWYD
But you seem to think that a 5 year old who bites is cute, funny, makes an amusing anecdote. It's not. And I can assure you that the parents of a bitten child wont find it cute, funny or endearing either. But, putting things into perspective, I really don't give a toss whether you bite your GD; give her a pat on the back or send her to join the Foreign Legion; it matters not one jot to me. But if not addressed, it will, at some point, matter to your GD.