IGN shares with us a sneak peak of a few details on the 3DS version of The Sims 3 Pets, along with the first 3 screenshots.  Special thanks to InfiniteSims for the link!

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Playing as a pet extends way beyond your mark on the living room floor. You can customize your own pet (choosing from dozens of feline and canine breeds) in the create-a-pet portion of the game, and then can choose to have offspring with other like-specied creatures in game (cat or dog) and set up your own animal dynasty. Pets have their own specifically-tailored wishes and lifetime happiness rewards like human Sims, and super-animal-and-3DS-lovers can even create families composed of just dogs or cats — an exclusive option for the 3DS.

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