So since Ada, daughter of David, who died in 1219, "cannot have been" the mother of children born after 1255, we have this document to understand:
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a copy of the patent or grant of creation to Sir William Brereton, of the Barony of Brereton, has since been procured and in that instrument such royal descent in Scotland is expressly recited and recognized in the following terms: "We, considering with mature deliberation the free and true services of Sir William Brereton, and that he is sprung from an ancient, noble and most renowned family, inasmuch as he is descended, through many illustrious ancestors, from Ada, sister of John, surnamed le Scot, 7th Earl of Chester, and daughter of David, Earl of Huntingdon, Lord of Galloway, within our kingdom of Scotland." (This quotation is found in Archaeologia, or Miscellaneous Tracts Relating to Antiquity, Vol. 33, p. 59.)
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In other words, the claim of descent from Scots nobility "was" accepted, and that "would not have been" based on an issue less marriage.
So either -
- someone fooled the Lord Lyon etc
- there "is" a valid descent by issue (mother and father to son, and on from there)
To understand the valid descent we can revisit the Latin of the inscription. And again my question:
Does "filia" ever, in medieval Latin, mean anything different from "daughter of" ?
To answer that I asked Mr. google, and he served me serveral interesting answers, the first being
Magnum Filiam = grand daughter in Latin
So - perhaps the word "magnum" fell off the inscription.
However Mr Google had some other possibilities. For one thing, the "more usual" term for grand daughter was, according to
http://freepages.genealogy.rootsweb.ancestry.com/~earlofdonegal/LAT...
granddaughter; sometimes great granddaughter - NEPTIS
There is also
http://www.rootsweb.ancestry.com/~gsfa/Latin_words.html
filia fratris/sororis: niece, daugher of brother/sister
filia innupta: unwed daughter
And
http://ancienthistory.about.com/od/familyanddailylife/qt/030609Rela...
filia, -ae. f. daughter
privignus, -i, m. stepson
privigna, -ae, f. stepdaughter
nepos, nepotis m. grandson
neptis, neptis, f. grand-daughter
I've uploaded a chart from the latter source here
http://www.geni.com/documents/view?doc_id=6000000026887826122