TFPL, July, 2004: As yet I do not have the evidence by which it has been ascertained that her surname was Delamere.  From 1912 to 1964 at least, it was unknown, as related in various surveys of the magnificent brass of her and her husband in Bedington church.

TFPL, Nov 2006: I’ve found a post by Ronny Bodine of 6 Dec 1999 which says that Isabella’s mother was Alice de la Mare and related to a Sir Thomas Delamere of Aldermaston, Berks.
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Apparently there is a manuscript in the British Museum (Landsowne 874, fo. 38 v.) by Nicholas Charles, Lancaster herald in which he writes:

"In Bedington Church, in Surrey taken the 17 day of June by me Nich: Charles Lancaster Anno Dni: 1611.
"In the windowes of the sayd church of Bedington.
...
(3)The same [Carew] impaling gu. 3 catherine wheels arg."

Also in this church to this day is a brass of Nich: Carew and his wife Isabella which shows 3 catherine wheels, without tinctures, of course.  This then give Isabella's arms which Fairburn's "Ordinary of Arms" identifies as Espec or Street.
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