Eileen, I think there is some kind of bitter lemon spray you can get in pet supply stores. You spray it on wires, and since the taste is nasty to cats, when kitty-boy bites down on the wire, he goes "EEEWWWWWwwww!!!" and is never again tempted. That's how it's supposed to work, I gather; I've never had need to try it myself. Something like vinegar might also work.
Prayers and good wishes to your family! Dearest little darling Amigo, PLEASE don't chew the wires! You know your Momcat and Soncat are both always looking out for your safety and well-being.
I meant," said Ipslore bitterly, "what is there in this world that truly makes living worthwhile?"
Death thought about it.
"Cats," he said eventually. "Cats are nice."
-- Terry Pratchett, Sourcery