private Object handleEventFact(Object tos, String tagName, String tagNameUpper) {
      if ((tos instanceof Person && EventFact.PERSONAL_EVENT_FACT_TAGS.contains(tagNameUpper)) ||
          (tos instanceof Family && EventFact.FAMILY_EVENT_FACT_TAGS.contains(tagNameUpper)) ||
          (tos instanceof EventFact && "CAUS".equals(tagNameUpper) && ((EventFact)tos).getCause() == null)) {
         EventFact eventFact = new EventFact();
         eventFact.setTag(tagName);
         if (tos instanceof EventFact) {
            ((EventFact)tos).setCause(eventFact);
         }
         else {
            ((PersonFamilyCommonContainer)tos).addEventFact(eventFact);
         }
         return eventFact;
      }
      return null;
   }