Karen Gurnak, age 12, of Youngstown, Ohio, for her question:

WHY DO SOME PEOPLE WALK IN THEIR SLEEP?

Sleepwalking is also called somnambulism. It is a condition during which a person who might be partly awake will perform various physical activities. Most sleepwalkers only sit up or stand near their beds. Some do walk about and a few have been known to perform even more complicated actions.

Sleepwalking happens with young children more than adults. The reason seems to be tied in with a period of worry or tension. After awakening, most sleepwalkers will not be able to recall their activities. Sleepwalking is harmless, although it is possible for a person to fall during his walk and injure himself.

It doesn't harm a sleepwalker to awaken him.