Scenario 2: Zechariah's Two Sons

John the Baptist and Jesus the Christ were the two sons of Zechariah, one with Elizabeth and one with Mary, no different than Abraham and Sarah and Hagar or Osiris and Isis and Nephthys.

• John was the first-born and Jesus the second-born, as is witnessed in ancient artwork which often shows John holding one finger upward and Jesus holding up two fingers. See this
• Several ''heretic'' sects view John as the true Christ and Jesus as an usurper. 
• John the Baptist and Jesus the Christ were two separate, opposing entities and movements - one hostile to Roman authority and one a sell-out.
• Perhaps Mary used her position within the holy family and her teachings derived from Zechariah and Elizabeth in order to usurp John the Baptist's birthright in favor of her own son.
• When Gabriel announced to Mary that her cousin Elizabeth was pregnant, Mary made haste to Zechariah's house by herself - perhaps to seduce Zechariah.