They are both domesticated once feral breeds if animals, both species have relatively short gestation periods compared to other mammals with up to 26 month gestational periods.
Puppies and kittens are deaf and blind when born but they do have fur about a week after they are born their ears are opening as well as their eyes. Both start discovering their legs around 3 1/2 weeks and by 4 weeks they are moving around pretty good but not very coordinated.
Both pups and kittens are weaned between 6 and 8 weeks old and are adoptable ready to leave mom and start bonding with their new human families.
Both species are highly adaptable and will imprint on other animals in the house, cats accept dogs, birds, guinea pigs, dogs, puppies etc and so do the pups, it’s all part of imprinting and socialization they both are pre programmed to do before they are born, the biggest difference is how much time is invested into their imprint training and their socialization. The more attention and work invested into the pets reduces the problems later in life or even up the road with training of basic obedience training and house manners.
Both species need rabies shots and routine vet visits and should be spayed or neutered depending in their sex unless you plan on breeding them for some reason other than to let them experience parenthood, there are thousands of unwanted animals already without adding more to he system to be destroyed.
Both species go through shedding seasons, some need specialty clippings, both can be either indoor or outdoor animals or a combination of both. Both species do better and are better as companion animals when they live indoors and only exercise outside but not live there 24/7.
People give both love and affection to their favorite species and some people dote on them, spoiling them, only the best foods and home cooking are good enough, and the pet food industries are making billions of dollars of people’s worries that they are not giving the best of the best and the average consumer pays several thousand dollars on specialty diets that were not really needed but according to the commercials your pet will lopive longer, be hapealthier, more fun to pl
There are many other similarities like shedding