How to give away pets!!!
So first you must become good friends/best friends with someone in town. Then under the friendly category when talking to them, ask them to move in BUT, instead of THEM moving in, make your pet live with them. So on the left side is your house. On the right side is theirs. Move the pets you don't want from the left to right side (along with the person you were talking to and asked to move in.)
More tricks, tips and cheats for this game are right here - The Sims 3 Pets cheats
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