Should I get a Yorkie or a teacup Maltese puppy?

Listen, never buy a teacup anything. The dog might look healthy, but genetically it isn't. Teacup dogs often have problems like liver shunts.
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Wait two years on the "teacup" pup. Then, if it's still in the land of the living, you'll see how "healthy" s/he is.

But then, even a badly bred Yorkie will have major problems. Don't support backyard breeding. If finding a reputable breeder is too hard for you–adopt.
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I'd go for the Yorkie, at least it's of a real size.
Yes the "teacup" runt is healthy *now* but 2 years from now have fun with those vet bills.
There is no such thing as teacup dogs, they are just extremely poor examples of the breed itself and typically live short lives.

To be honest I'd get one from a shelter or a real breeder that actually cares about the dogs.

Add:
*sigh* if he CARED he wouldn't be breeding them so poorly. Or maybe he's just not educated (*gasps* and therefore shouldn't be breeding) and doesn't realize how sickly teacup dogs can get and how his negligence in breeding is only contributing to a larger problem.
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First of all there are no such thing as a teacup maltese, poodle or anything! Unless it is a actual teacup itself. I am not trying to be rude or anything I am just telling you the truth. The whole "teacup" thing started when bad breeders, pet stores, and puppy mills came up with an idea to sell runts for more money. Yes "teacup" puppies are just runts that puppy mills and such try to sell for more money.
But if you have done you research on both breeds and have done you homework then get one of the puppies. Both breeds are great.
Please be a responsible owner.
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I work at a animal shelter

no.
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maybe you need to not have any dog. but even though you will the yorkshire terrier is what i would choose. a teacup maltese is just the runt of the litter. the whole teacup thing got started by puppymills, backyard breeders… etc
anyone who thinks that a tea cup maltese exist needs to be mentally evaluated.
the breed comes in one size. that size that they come in is already small. the smallest they will ever be is when they fit into the palm of your hand at birth.
see if that teacup maltese is still living 2 years from now. be prepared for your vet bills to sky rocket if you have a maltese.
anything smaller than a maltese that is what you call a maltese. may not even be a dog.
why would anyone even want a dog that small.
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i am a first time mutt owner. a very proud mutt owner.

http://www.petfinder.com

Sounds like your uncles friend is a puppy mill. You should not buy from a puppy mill.

Stay away from anything called a "teacup" ! ! ! ! ! ! ! ! ! ! !

There is no such thing, they are just sickly runts bred to sickly runts only producing more very poorly bred sickly runts. With their health problems you will spend a fortune at the Vet.

Go for the Yorkie as long as it is not a teacup. But be sure to get a certificate of health from the seller showing that he pup has seen a Vet & has a health clearance.

In fact I would look for a dog from another source. I would not trust this friend of your uncles.
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I'd choose Yorkie. I have one and she's very smart and loving. I avoided getting a white dog because of their eyes making those streaks seems gross and would be harder to keep clean.
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OK, for starters, there is no such thing as a "teacup" Maltese. Teacup is a marketing term used by unethical breeders to describe dogs bred to be extremely small, generally with no regard to the overall health of the animal. These are the types of breeders you should be avoiding!!

I would suggest that before you decide on EITHER breed, you take the time to educate yourself on the breed FIRST. (If you had, you would know that "teacup" is a taboo!) Having a good overall knowledge about the breed(s) will better enable you to make wise decisions when searching for your pup.
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Yorkie breeder 10+ years