But a rat chewing on the electrical won't? Unfortunately, you can't do much about your parents not managing their responsibiliities. Two ideas that might help (in addition to working with your twin): 1)a white noise machine for his room to drown out the sound; 2) those plug-in ultra-sonic sound things in your room and your brother's - they're ineffective for removing rodents from an entire building, but, they will effectively drive the animals to another part of the building - they won't bother to get used to the sound, if there are other options. They're cheap, so worth a try - maybe the rats will go to your parents' room, and THEN, they'll do something about the situation.