Check out this preview of Pets by EL33TONLINE.
The Sim 3: Pets will be a new standalone game for the Xbox 360, PS3 and Nintendo 3DS, and an expansion pack for the PC. The pets will be fully controllable, a first for the series, so you’ll be able to command them to hunt, climb, dig and more, just like your normal ‘human’ Sims. Gamers will be able to enjoy over 100 breeds of cats and dogs, while PC gamers will also be able to adopt horses. Of course you’ll be able to customise your pet across all platforms, giving your pet traits, another first for the series, as well as creating new breeds which you can share with your friends.
3DS owners will be able to use the built-in pedometer to collect Play Coins and earn Karma Points. You’ll also be able to gift or trade your Sims pets with your 3DS friends using StreetPass. Most importantly, you’ll be able to have up to three controllable Sims, which can all be pets if you choose.