DH and I have just had the mother of all rows about whether it's unsafe for 4.5yo DS to wind his window down when it's hot. The compromise we've reached is to try and find some kind of gadget that allows him to wind it an inch or so but no further. Does such a thing exist? I've found locks online that make it impossible to wind it at all, but ideally I'd like him to be able to wind it a little bit a) to avoid him overheating in the summer and b) to allow him a little bit of autonomy/control over his environment. Any ideas?