My brother’s ex-girlfriend is hitting on my older sisters fiance’. We all were kinda close to her (my brothers ex)even when they split up she still came to family functions and thats where it happend at one of the functions she lifted up her dress and exposed herself to him when the two of them were alone. since then he told my sister to stay away from her but then one day he called the ex over to his house when my sister wasn’t there he said it was because he was drunk. Should i say something to her or just let it play out?