Well most people don't like the smell of pee, especially old stale pee. So that's probably the main reason people don't all pee on the sidewalk - oh, and privacy of course, someone might see your privates which might might embarrass them, or you.
I don't think it's bad for the sidewalk itself, but I'm no sidewalk expert.
Will your parents find out? Depends on a lot of things, including how often it rains where you live. After rain the smell will be gone.
BTW i have 2 boys who both like to pee in places that are considered inappropriate - e.g. middle of the playground, or BEHIND the toilet seat in our house.
The latter particularly is a problem for me, the smell of old stale pee in a closed room makes me feel like I want to puke every time I go into our bathroom. I clean it like twice a day but they pee much more frequently than that. Explaining how it makes me feel doesn't help - they're too young and just don't understand. If I could understand WHY they're so fixated on peeing in particular places, maybe I could figure out some compromise.
Think you can help?
Any insight much appreciated.
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Father of 2 children diagnosed with ASD, and 2 more who have not been evaluated.