Gardner [1996: 236] proposes three children for Jesus and Mary Magdalene: Damaris (Tamar), b. AD 33 (in a later edition [2000: 174] she is married to St. Paul); Jesus II The Justus (Gais/Géso), b. AD 37; and Joseph The Rama-Theo (Josephes), b. AD 44. He also claims that Joseph of Arimathea is none other than Jesus' brother, St. James the Just. He appears to base this information on the controversial work of Dr. Barbara Thiering and her pesher technique of interpreting the scriptures.
Gardner shows no descendants for Tamar, and a son (Galains or Alain who died without issue) for Jesus II. The only line that continues is through Joseph, the younger son. His descendants become the Fisher Kings depicted in the chart below.
Chart 1. Derived from Bloodline of the Holy Grail. Image © 2008, Bloodline: The Evidence.
Of interest is that in L'Estoire del Saint Graal, the first part of the Lancelot-Graal cycle, the character Bron (who here is married to Joseph of Arimathea's sister) has the following line of descendants: Joshua-Aminadap-Carcelois-Manuel, etc.
Chart 2. House of Lancelot and the Fisher King. Click to enlarge. Image courtesy of Timeless Myths.
The Fisher Kings in Wolfram von Eschenbach's Parzival are Titurel-Frimutel-Anfortas.
Chart 3. House of Parzival. Click to enlarge. Image courtesy of Timeless Myths.
Note the similarity in the names. It appears that to create a line of descent from Jesus and Mary Magdalene, Gardner grafted together two separate lines of Fisher Kings from two medieval fictional Grail stories onto Thiering's theory.
It is interesting that Gardner says this information is available publicly. In a lecture (Yelm, WA, 30 April 1997) he is quoted as saying:
It was never any secret when my book came out [Bloodline of the Holy Grail], for the majority of these people, that Jesus was married and that Jesus had heirs, because it was written as such in very many family archives, not necessarily just private but in the open domain. The published papers of Mary, Queen of Scots talk about it at length. The papers of James II of England, who was wasn't deposed until 1688, talk of it at length. [Nexus 5/2 (February-March 1998).]
A more specific citation than "published papers of Mary, Queen of Scots" would have made it easier to corroborate these claims.
SOURCES: Laurence Gardner, Bloodline of the Holy Grail: The Hidden Lineage of Jesus Revealed (Shaftesbury, Dorset: Element Books, 1996). Illustrated edition (NY: Barnes & Noble Books, 2000).
"Genealogy: Houses of the Grail Keeper and the Grail Hero," Timeless Myths (Retrieved 23 Dec 2008).