People who try the trick generally choose a plain or lightly scented bar and keep it dry. Anyone with sensitive skin should avoid strongly perfumed products that could cause irritation, particularly if the soap comes into direct contact
with the body.
For many families, the soap trick is simply one of those inexpensive remedies passed down by parents and grandparents. It costs very little, requires almost no effort, and gives people something simple to try when nighttime discomfort becomes frustrating.
So, while your aunt may not be following a scientifically proven treatment, she is certainly not alone. A bar of soap under the sheets has become a curious piece of traditional household wisdom—one that some people continue using because, whether through comfort or coincidence, they believe it helps.