I decided to replace the switch in my son's room anyway, because the newer switches seem to make the fans run much quieter. Now with the new switch, both the fan and the light work in my son's room. As you suggested, there is probably a problem with wire connections or something on the light unit in my daughter's room. With the new switch, when I switched the lights on the very first time and pulled the chain, there was a very brief flicker of light on the bulb filament. I'll check the wiring on the lights. And thanks for the info on the bulbs. I'll check and be sure to stay within recommended wattage. I'll keep checking, and post my findings. Thanks for the reply.