Is A Toy Dog Also An Unhealthy Size For A Dog?

A reader asked..
I know teacup dogs have all those health issues and are sickly runts, but what about “toy” size dogs? Do they also have a large chance of getting illness’s and can you get them from animal shelters to? And is there size dangerous for them also like teacups since they are like just above teacups on the size list? thx!

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