English has a popular phrase, "don't throw out the baby with the bath water". There are many theories about its origins. Some people say it originated in the medieval times, others say it is from Germany. We have probably used this phrase before, but don't really know what it means. It means that in the process of getting rid of a bad thing, be careful not to do away with a good thing
One explanation claims the phrase was inspired by the living conditions that prevailed during the Middle Ages. Most people could hardly afford to have a bath as water was scarce. When they did bath, all members of a family used the same water. The father, as the head of the house, would bath first, followed by the mother and then the children in the order of their birth. Naturally, the baby would be last. You can imagine how dirty the water would be at the end, probably enough for a baby to risk being discarded unnoticed when the tub was emptied.
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