Zelophehad the genealogist was drawing a family tree for
Nathan Sourmash, but a disk-crash destroyed most of his work.
All he's recovered are twelve names (in addition to Nathan), and
some tidbits of information linking them.

From these clues, draw a family tree depicting each of the 12
person's exact relationship to Nathan.  (You may need to add
one or more unnamed ancestors to link all 12 to Nathan.)

Clue 1:  The 12 people include five women (Sabina, Tamar,
Ursule, Valpurga, and Wilmot).  Their husbands were Aella,
Benno, Cadelon, Donogh and Gregor, in some order.

Clue 2:  The 12 people include seven men (five just mentioned,
and Ephraim and Fjolnar).  Each had children only by a single
lawful wife.  Each of these seven wives had children only by
a single lawful husband who was not her own father, brother,
son or nephew.

Clue 3:  Three of the men did not have any brothers.  Aella was
Donogh's brother.  Gregor was the brother of the seventh man.
(These are full-brothers, not half-brothers.)

Clue 4:  Ursule is Fjolnar's granddaughter.
Neither Sabina nor Wilmot is descended from Fjolnar.

Clue 5:  Ephraim had no daughters.  His grandchildren included
at least three of the 12 people.

Clue 6:  The set of 12 includes both parents of Nathan,
all of his grandparents, and all of his great-grandparents.
The set includes exactly three of Nathan's great-great grandparents.

Clue 7:  Valpurga was Tamar's mother and Wilmot's daughter.
Aella was Benno's father.

Comments:
(1) I'm somewhat confident the puzzle has a unique correct
solution.  Money-back guarantee.  :-)

(2) FWIW, the pedigree is the actual official pedigree of a
19th-century King, though with names changed.

(3) You needn't use Ascii art to draw a family tree; the
Ahnenreihe system represents a pedigree with a list of
number-name pairs.

(4) This puzzle may be difficult but should be straightforward
and doable for someone with good grasp of kinship charting.

Dearest regards, James Dow Allen (mail address: jamesdowallen at gmail)

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