my son is becoming curious and my mother-in-law caught him peeping at his sister. how can i make him understand how wrong this is without making him feel like a pervert?
Well I wouldn't worry too much about it, I shouldn't think there are many boys that haven't sneaked a look at their sister ... thing is not to make him feel all weird about it, its natural curiousity that's all. If you must mention it then I think I would say something like 'well we all like our privacy in the bathroom don't we .. and then give him a pointed knowing stare ...' he will know what you mean without having to make a big thing of it.
don't like your use of "how wrong this is". it's not wrong, he's just being naturally curious. If he was sneaking into girls toilets to peek, THAT would be wrong, but checking out your sisters bits is just what happens in families, isn't it???
I wouldn't worry too much, It won't be long before your daughter clocks on to this and will give him a roasting herself. He's not doing anything wrong at all, as you said yourself - he's curious.
It's not wrong, perfectly normal for a young lad and I personally wouldn't mention it. Lads have been doing that for thousands of years and there are several refernces to it in autobiographies etc of the great and the grand. As Lore says she'll catch him out if he makes too kuch of a habit of it and then heaven help him :)
I agree with others comments. Its a bit harsh for you to judge your son in this way. What he is doing is natural. The same as getting embarrased whilst walking through the bra and knickers department or unintentionally seeing girls breasts when changing for PE at school. My boys went through similar but we just treated it as part of growing up. Your mother in law shouldnt be putting her two penneth in - its no big deal.