Why keep the belly button warm?
A child lifts their shirt after a bath, and an adult immediately says: cover your belly. The warning can feel oddly specific, but it belongs to a bigger map of vulnerable body areas.
Care before discomfort
Chinese household advice often circles around cold wind, sudden temperature changes, and exposed body areas after bathing or sleeping.
The belly button becomes a symbolic and practical center of that care language.
How to write it
The point is not medical certainty. The point is to understand a family language of care.