Pets in our world
Dogs don't chew shoes out of spite. Cats do not pee on a bed to get even. Birds do not scream to invoke anger. Ferrets do not hide car keys for a specified reason. These are behaviors natural to animals. When it happens, it is wrong to say that the pet is acting out spitefully, but it should be noted pets are just animals living in our confusing world.
Turn off the light
If there are no live plants in your freshwater tank, but there are a few windows in the room, the natural daylight in the room will be fine for community fish. As an added bonus, you will get much less algae growth on the sides of the tank if you leave the light off during the day, as algae needs light to grow and thrive. So leaving the light off will not really harm anything.
The bulbs in aquarium lighting hoods are expensive, so the less you keep them on, the longer they last.
Vaccinate the ferret
The chances of a ferret contracting rabies are slim, but it should be vaccinated nonetheless.
Ferrets are treated as second-class citizens by some municipal health departments for unknown reasons.
If someone claims to have been scratched by a ferret, health departments could insist the ferret be euthanized and its brain tested for rabies if no documentation of a rabies vaccine is found.
Remember a ferret does not necessarily have to actually bite or scratch anyone.
The accusation alone is enough to bring on this trouble, but if there is a letter from a vet stating the ferret has been vaccinated, the whole problem just goes away.
Ringworm is a fungus and can be passed from animals to humans. In some cases, the fungus has spread from an infected dog to every human family member as well as the other animals.
In other situations, the fungus was diagnosed in one pet and was cured without it spreading to anybody. The medicines and treatments for ringworm work well, and the situation is correctable.