lost child

so big sister was great last year after school about asking if she could go somewhere so very rarely did i "lose" her at school while i was working.
little brother however is very slowly learning that I need to know where he is. so again today i was telling him why he needs to tell me where he's going, threatening to make him stay in my room if he doesn't tell me where he's going etc etc...
to which he told me
"mom you should just get me a few packets of that sticky paper (post-it notes) and i'll leave you a trail to follow so you can find me"