Likely NOT very healthy. Selectively breeding for tiny size like this creates a myriad of health and behaviour problems. These are designer dogs for people with no concern for the overall health and welfare of the domestic dog.
However dogs are not at the same size, nothing is the same, difference in everything.
From the horse-like Great Dane, to the short-legged Corgi, to the tiniest of tea cup breeds, it’s hard to believe that are all the same species. It’s even harder to believe that some of the smaller ones are actually descendants of one wolf-like ancestor, but it’s true.
While they might not look like dogs, they’re still ridiculously adorable. Here are some of the tiniest and squishiest “dogs” out there: