Bit of a random one but DS14 is constantly picking his skin, nails and worst of all his nose. He's way too old to get away with doing it in public but honestly doesn't seem to care - his finger is almost permanently up his nose and then in his mouth. When he has a cold he scoops the snot out with his thumb and eats it.
Sorry, sounds so gross and ridiculous written down but the fixation is totally out of control and I don't know how to make him stop. I'm on his back the whole time about using a tissue and telling him it's grim but he just rages at me. He has no social shame and says his friends just think he's the crazy one who does mad shit the whole time (he's at a boys school so no girls to add a civilising effect).
I'm honestly at my wits end and it's terrible for his health - he picks up every bug going.