Imagine you’re a Target employee and you see a baby plummet from a high shelf. You rush over to help the baby’s family, heart pounding, but they appear totally unbothered. In fact, they’re laughing.

To some, the dolls, known as reborn dolls, provide comfort, escape or just plain fun. But politicians across Brazil have tried to pass bills banning the dolls from public spaces. To some, the dolls, ...