I've been thinking about it for a while... and to me it seams like it shouldn't be very difficult to make at all, just, like other things, tedious.

We would need to figure out how to add a new option to Create-A-Pet, that when selected, would allow you to chose to create a Toy sized dog, along with the existing small and big sized dog breeds.

Making the dog smaller, just thinking about it, should be fairly simple. The size would be the same as a large dog breed puppy. It would be smaller than a small dog breed, thus being a toy breed.

Some breeds that would be included as a Toy breed:

Chihuahua
English Toy Spaniel
Italian Greyhound
Miniature Pinscher
Poodle
Pomeranian
Pug
Shih Tzu
Silky Terrier
Toy Fox Terrier
Yorkshire Terrier

This, like all "super-mods" as I like to call them, is, to make, easier said than done.
If you can think of any other breeds that are normally toy sized, please share. If you have any knowledge concerning the production of this mod, please share. :D

Affenpinscher
Australian Silky Terrier
Chihuahua (Long Coat)
Chihuahua (Smooth Coat)
Chihuahua (Short Coat)
English Toy Terrier (Black and Tan)
English Toy Spaniel
Italian Greyhound
Japanese Spaniel
King Charles Spaniel
Lowchen (Little Lion Dog)
Manchester Terrier]]
Miniature Pinscher
Pomeranian
Poodle (Toy)
Silky Terrier
Toy Fox Terrier
Toy Manchester Terrier
yorkshire Terrier
Xoloitzcuintli
Maltese
Bichon Havanais (Havanese)
Bichon à poil frisé (Bichon Frise)
Bolognese (Bolognese)
Coton de Tuléar
Petit chien lion (Lowchen, Little Lion Dog)
Caniche (Poodle—all three sizes are in the Fédération Cynologique Internationale Companion and Toy Group)
Griffon belge (Belgian Griffon)
Griffon bruxellois (Brussels Griffon)
Petit Brabançon (Small Brabant Griffon)
Chinese Crested Dog
Lhasa Apso
Shih Tzu
Tibetan Spaniel
Tibetan Terrier
Chihuahua
Cavalier King Charles Spaniel
King Charles Spaniel
Pekingese
Japanese Chin (Chin)
Epagneul nain Continental (Phalène, Continental Toy Spaniel)
Papillon
Kromfohrländer
Bouledogue français (French Bulldog)
Pug
Boston Terrier
Russkiy Toy

Those are all the internationally recognized toy dog breeds, although we definitely don't need them all.Maybe we could have a poll and include the top 15? Sorry for any repeats.