It sounds like a bad movie plot: An eccentric millionaire leaves his fortune to his... cat?! But real life isn't Hollywood. Pets cannot be beneficiaries to an estate. But that doesn't mean you can't write your four-legged friends into your will and ensure they have a great life in the event of your passing.
One study found that about 4 out of 10 instances of pet re-homing occur when a friend or relative gives a pet to another friend or relative, primarily because of reasons having to do with cost and housing issues. Proper estate planning can circumvent these problems.