Update:

My dad called the animal control people this morning because there is a humane society who sometimes go into neighborhoods and collect feral cats to spay/neuter and release them back into the neighborhood. He called and left them a message. The animal control people said three people have reported missing cats in our area (and we know there is more, like our next door neighbors who have not reported). They also said it is likely they could have been attacked by a wild animal, as we live among bobcats, cougars, raccoons, etc. And I believe I just saw my neighbor's cat recently, I believe I saw it across the street.

I am hoping and praying that Cleo is safe.