Chocolate contains a toxic substance, theobromine, which is harmful to pets.
A pet exposed to bitter cold that becomes lethargic, depressed, and weak, could be hypothermic. Call your veterinarian immediately. The sweet, lovely green pool of antifreeze on the driveway is an often deadly drink for dogs and cats. Even a small lick by a small pet is enough to poison it. Try a night light or leaving the front of the cage uncovered.