I do not know of any medicine in Haiti that would do that. The woman may have told you about lalo (aloe) or a plant like aloe which they cut and slice and rub on the kid’s finger. It’s bitter. Haitians also try other things like covering the finger with a sock or smearing it with piman (hot pepper) or kaka poul (chicken feces) – imagine the handful of harmful bacteria a child could ingest with that last one. They say that most kids eventually grow out of this behavior, but if he/she doesn’t and you are worried then talk to a doctor.
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