Old folklore of Bulgarian and Turkish origins talk of deceased husbands coming back as vampires and impregnating their widows. A widow was expected to remain celibate after her husbands death until she would remarry. If she was to become pregnant during this time of mourning she could easily blame it on hear husband who had obviously become a vampire. The offspring of such a union, called vampirdzii in Turkish and gloglave in Bulgarian, were often admired and believed to have great power in hunting down and destroying vampires. 

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