No, it shouldn't. Hint -- never normally turn off your Mac. He must be used to how Windows gets unstable after too many sleep cycles and is afraid to use sleep. Only turn it off to move it, are unplugging power cords, or are adding memory.
He has, however, identified a genuine, which has drawn a lot of comment on the Mac sites. Closing the lid of a MacBook, or letting an iMac fall asleep, sends OS X to standard sleep mode. It is possible to inadvertently awaken by triggering a paired Bluetooth device, such as your mouse. If this happens inadvertently while carrying your laptop, this can cause the dreaded "red hot laptop in bag" syndrome. You can, however, disable Bluetooth awakening in Preferences. There is another, related problem: if you have a laptop with extra batteries, Sleep mode is insufficient when swapping batteries. There is a "deep sleep" mode that is supposed to write the contents of memory to disk in case you do change batteries during sleep - but it doesn't work yet. For my new Santa Rosa laptop, I have to use a custom French widget to deep-sleep the machine when I change batteries; at other times, I can use standard sleep.
Let's hope they fix all this in Leopard.
Thanks for the info. I don’t have a MacBook and have the wired mouse, so everything works fine. The PS3 and Wii are Bluetooth, but the iMac hasn’t even tried to recognize them. If a kid hits a key it will wake up and then go back to sleep, no problem.