Check it yo! @Blackgarden interviews @simgurugraham!
H: So if you had a rodent, could you take it out of its cage and play with it?
G: Yeah, you can take them out, but if you leave them out for too long, leave them in your inventory or whatever, they can escape into the house and they might disappear on you. And of course the birds have lots of stuff, you can teach them to talk, they might get out and fly around the house.
H: What about interactions between different kinds of pets? Can a cat make friends with a horse?
G: Yeah they can and you might find certain relationships easier than others. Cats and dogs are notorious for not getting along, so they can form a relationship, they can become close friends, but it might be a little bit more work. Alternatively, dogs will form instant relationships with Sims, they’re man’s best friend right? So there’s definitely different things that are taken into account there but all the different types of animals can have different interactions with each other.
H: What’s the new supernatural creature?
G: That is the big thing for GamesCom, we’re talking about the unicorn, and revealing that for the first time. It is the new creature in the game, and we’re really excited for that. We’ve obviously never had a unicorn before, so it’s a brand new experience for fans and players. It’s very cool it has all these mythical magical abilities. The unicorn’s going to be very exciting for players.
Source: Sims 3 UK Facebook