The neighbor that sings but does not think

One of our next door neighbors is a music teacher. He is in his late 50s and lives with his wife. Sometimes they come to their attic (we life in the attic next door) and they sing on the piano and vocally. Till now I had no problem with them and said “good day” whenever we met. 

At the beginning of last week I started to feel a bad smell in the bedroom, but I said that it had to be something from outside. Two days later the smell became really bad and then I said that it’s the flowers that got bad and threw them. The smell got only worse. We couldn’t and still can’t sleep in our bedroom for the last week. We asked the neighbors if they used rat poison and the singing one says that he did…

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How CRETIN you have to be to use rat poison in an old house… especially at the higher floors??? I asked him why did he do that and I got the answer that he thought it was no problem and that he only used a small amount of poison (after all he didn’t try to kill an elephant). This problem is not yet solved since the Handy-man is on vacation and we need to take out the floor to search for the dead mouse… For sure the neighbor will pay for his stupidity.