Hairless cats like the Sphinx feel the cold in winter. Consider a t-shirt for extra warmth. Their coats also give off skin oils and a T-shirt will help to keep upholstery and linen clean.
If you cat and dog has a lot of static in their fur, try using dryer sheets. Run one lightly over your pet’s coat to take out frizz and the friction. Don’t forget to wash your hands afterwards.