Ah lol.. You should see my house when one person Farts

Even my DD know thinks it is hilarious..

I expect my boys to say excuse me however. They don't always but I do remind them..

I think the age I would expect some understanding would be around 4. My 4 yr old is grotty lol but he actually asks us now.. Mum can I fart in this shop.. unfort sometimes he follows that sentence with.. oops I already did.. Can ya smell it *sigh*