Somewhere out there, Mother Nature is laughing at us, because she gave one little Shih-Tzu puppy a bark that sounds less like a canine warning and more like a squeaky dog toy trapped inside a furball.

Life can be funny, and not just for humans. Studies by various groups suggest monkeys, dogs and even rats love a good laugh. People, meanwhile, have been laughing since before they could talk. "Indeed ...

It has been more than a year since Stephanie Nunez last heard Amanda Moreno's squeaky laugh. "She had a laugh that me and her loved ones ache to hear," Nunez said. She described spending an evening ...