Take a look at the base of the plant. If you see some black rings around the base of the stem where it meets the soil, you have a rot. Drooping leaves CAN mean it needs more water but begonia are hard pressed to show it unless it is SEVERLY underwatered. It seems something more than lack of water if half are doing it, adn half are not! Keep the neighbor's cat away from there!!! There is a really good product called "critter ridder" by havaheart.. (it's organic) that works AMAZING!!!! sprinkle it on the ground and the cat should stay out of the bed! As far as the begonia, try to upload the pictures if you can so we can see them!!! It is kinda hard to diagnose some plant material if you can't see it!! good luck!!!

Thanks again orchidluver. Can I buy Critter Ridder at Home Depot? Will try that and I will take a look at the base of the plants. If I can figure out how to upload pictures I will. Also, you answered my question about pinwheel jasmine, are you in Miami? I was wondering where I can buy the Holly Tone. Thanks