If a corporation can be a person, why can't a chimp?
Step 1: Create a corporation called Chimp Inc. and make its owner a chimp named Bonzo. (People can leave their fortunes to a pet cat, they should be able to leave controlling interest of a corporation to a chimp.)
Step 2: Once Bonzo the chimp has control of the Chimp Inc. corporation, have Chimp Inc. buy Bonzo the chimp.
Step 3: Bonzo is the sole owner of Chimp Inc.
and the only property of Chimp Inc. is Bonzo.
Chimp Inc. is a legal corporate person.
Chimp Inc. = Bonzo the chimp.
Therefore Bonzo the chimp is a legal person.