When you have an extremely tiny dog, you must be very aware of certain elements....
The weather - While all small dogs should be protected from harsh weather, an undersized Maltipoo especially should be protected with a coat (sweater) and doggie booties if there is ice and/or snow. Also, ice melt can be quite an irritant to the paws and booties (or paw wax) will protect them from that. For very cute yet protective vests, sweaters, coats and more, look to the Maltipoo Specialty Shoppe
Weight Loss/ Gain - When you have a pup who is just so tiny, one must be very careful that the dog does not lose or gain significant weight in a short amount of time. Being so small, a loss of just 1 pound can be critical to their health. Likewise, overweight dogs can develop a host of health issues.
Sleep - You will want to be very careful if you wish for your dog to sleep in your bed. An owner could be fast asleep and accidentally roll over their pup...This has happened and the results can be devastating for such a tiny ball of fluff.
Since there is no set weight standard by the AKC and the Maltipoo is not yet recognized as an official dog breed, one cannot say that there is "no such thing as a teacup"....However do keep in mind that for any other dog breed there is no such thing as teacups..... There are no teacup Pomeranians, no toy Chihuahuas... it is a made up marketing term to lure in potential puppy buyers into thinking that they have a special dog.....set apart from "normal" dogs and a separate variation.
Therefore, it is recommended that if you are looking to buy a Maltipoo, that you look for a breeder who is producing puppies with an estimated adult weight of 5 to 12 pounds.
If you already have a Maltipoo that falls far under the weight range, do follow the above advice and look to the PetMaltipoo eBook
for all the care that is needed.