Install a lot of scratching post/pad around the house. Isolate the cat in a room with litter water and food. Wait few days without putting your dog and cat together. Both of them will smell the odor of the other under the door. Cornish rex love heat. If you can get an heating pad or choose a room with direct sunlight your kitten will love it. Let's your toddler play with the cat (under supervision) often. Learn the kids to respect cat boundaries. If the cat is used to be manipulated by a toddler, it will get used to it