Nobles and Ishara's blood - Edit 1
Before modification by Zeratul at 03/04/2012 03:01:09 PM
Unlike Elayne and Rand, for Gawyn, marrying someone like Egwene means his line will count as commoners (She has not a drop of Ishara's blood), no longer holding any power or able to marry any noblewoman, but that issue isn't even raised in the series - even Elayne is beside herself with joy at the prospect of Gawyn and Egwene as a couple (you would rather have expected, in a real world setting, that Elayne would at least have lamented the fact she lost Gawyn for a political wedding between the future First Prince and the daughter of a House with a strong bloodline, Norwelyn for example).
Since when all the nobles in Andor are required to have Ishara's blood, and only matrilineal descent counts for that? All those hundreds of years there surely have been plenty of commoners raised to nobility. Elayne made Birgitte a noble and she doesn't have any Ishara blood.
Commoners can marry nobles in Andor anyway, even the Queen.
Besides, politically her brother getting married to the Amyrlin is about the most useful marriage possible for Elayne. Sure, she and Egwene are already best friends, but an additional link doesn't hurt at all, strengthen this tie and makes the connection public.