I usually get my 5 year old girl to at least squat behind a car when she's caught short in the street. These kids honestly when will they learn to "make sure you go for a pee before you leave". Tiny bladders though at that age. Said 5 year old (who was 4 at the time) was caught short in a hire car in a traffic jam in the middle of Harlem, right outside the Apollo as it happens, after making her hold it until she was practically crying we had no choice but to let her piss in a tuppaware pot and then pour it out on to the road out the car door. LOL as they say.