Older and smaller pets feel the cold more than most.
A dog jacket will keep your dog warm and toasty when they're out on walks.
During the really cold nights, consider moving your small furries inside where its warm.
You can also purchase heat pads that slowly release heat during the night - perfect for when the temperature drops. But be wary that pets must be able to move away from heat source so they do not burn themselves.
Wherever they are, don't forget to check your small furry friends regularly!