do soundproofing panels stop sound from outside the room? my sister is so goddamned loud. every day the first thing i hear is her either screech/laughing like a witch, or screech/crying like a bitch. i can't take it anymore. nothing else has worked to keep her mouth shut, material solutions are all that remain. I can either build stuff to keep her out, or i can kick her ass again, but that's not an option.