My 4-year-old son will not let me drink any iced beverages. Because I will get a stomach ache, he says. Where did he learn such nonsense? I ask myself, as I reach for a tepid glass of water.

It came from his ayi, the lovely Chinese nanny who looks after Ben every day after school. She is imparting many such nuggets of wisdom on my son. Another one is, eating cherries can help ease your sore throat. What seems random and arbitrary to me is actually a collection of instructions handed down from generation to generation on how to maintain a balanced and healthy life. (Many of them seem to involve drinking lots of warm water. In fact, when in doubt, drink lots of warm water.)

Every culture has its own set of “old wives’ tales.” They tell us how to behave and how to take care of ourselves, and they are told mostly through our mothers. Many such beliefs have been debunked by modern science, but we still believe in them and pass them onto our children. It is a kind of security blanket that we carry throughout our lives, a kind of mental how-to guidebook.

I am so glad that by growing up in China, Ben has the benefit of the Chinese version of old wives’ tales. Thanks to our time in China, he will have not just one but multiple sets of such beliefs to turn to in times of need.