That sounds horrible. I'm sorry your family had to go through that :C I know exactly what you mean about their infestations spreading. I remember the first house my mother got us into, we had that issue. Next door neighbor was a death fat. The housemate was also death fat. Their backyard was a cluster fuck of junk, rotting wood, etc. Every kind of north american vermin you can think of was calling that dump home. Rats would scamper frequently from there to near by houses, roaches never stopped showing up even if you bombed repeatedly. City got onto them, and somehow over the years it all got cleaned up. They moved several new sheds in there, and the worst of the junk is stored in there. Since the clean up we had no issues. Then the house behind us got a hick fat military family, they ran that building into the ground and we have vermin problems until they disappeared. The building was demolished. The destruction they did over 2 years was that bad. It's why if I ever have to look for another place to live, first thing I want to look at is who the neighbors are. I don't want to live near death fats if I don't have to. Their fat, and associated issues affects everyone.