I didn't witness this but I read that prior to the arrival of the Spanish, the dead (who at the time were embalmed) were taken out of their tombs. Friends and family members would dance with them, walk them around the cemetery, eat a meal with them and then put them back in their tombs. When the Spanish arrived they outlawed this ritual. So today, a family member often dresses up to look like a dead person and appears at the family reunion at the grave. He or she takes part in the feast that has been prepared and asks how the family has been over the past year. Sometimes the 'dead' person gives advice to the children. When the day ends, the children chase the person in the costume out of the cemetery just to be sure the soul of the real dead person doesn’t give in to the temptation of inhabiting their body in order to remain among the living.
These are the 'tantawawas' or bread babies that I bought in the market.