Their personal hygiene to the point where it's not even funny but whenever I confront them or speak to my mum about it I'm completely ignored or they see it as funny. My brothers favourite excuse for his poor hygiene is 'I do physical exercise'
But I don't think exercise is a good excuse? When I say they lack personal hygiene I mean they won't;
Wash their hands - even after using the bathroom, clean under their nails, my brother specifically refuses to cut his toenails/fingernails - my mum/dad have to do it for him, he is a teenager keep in mind.
Recently one of his toenails was so long he tripped over it also all under his nails is completely black/brown. My brother will also go an entire week without showering or will happily go to sports, get absolutely soaking in mud to the point his legs are brown - then go lie on bed without washing his legs.
This is just some things they do, there are other things not mentioned but I think you get the gist. Don't know how to approach this subject with them cause them and my mum seem to completely ignore it/brush over it.