I have a much loved nephew who is 13 and we have a great relationship. I have a good relationship with my brother and SIL but there have been times when we've had different opinions about our kids and I can sense they are wary of me. We parent very differently and because we are close we have had various differences of opinions over the years. They are both professionals/very busy and my nephew has been expected to just get on with it in regard to personal hygiene for many years.
The situation is that for some time, years infact, I have noticed more and more that my nephew smells. It's a combination of body odour and unwashed uniform. I at first ignored it, some months ago I had a casual chat to my brother but he asserted that he plays rugby all day at school and he's just a whiffy kid. My SIL wasn't happy during that chat and was quite defensive and has been a bit cold ever since. I haven't broached it again but for his birthday I bought him some computer games and some hair gel/smellies which he liked but obviously doesn't use. More recently I noticed that he has had his eyebrows threaded (they're quite heavy) and when I asked there were murmurings about him being teased. I can't help but think that there might be more to the teasing than his eyebrows.
AIBU to talk to my brother more seriously about this or should I just let it go?