I think Queen Victoria was the only other monarch who lived to see her great grandchildren, she didn't grant them arms. I think there was some speculation or suggestion on the part of Victorian experts that great grandchildren would or should receive seven pointed labels. Anyway, no member of the Royal Family has received one.
Quite correct.
While it would be logical for the son of a member of the Royal Family whose arms bear a label of five points to be granted the same arms but with a label of seven points, I can find no evidence that it ever happened.
Here is a link to a page that I think sets out accurately what has happened with royal marks of cadency over the centuries:
http://www.heraldica.org/topics/britain/cadency.htm
Note that both Edward (future King Edward VIII) and Albert (future King George VI) were not granted arms until 1911 and 1912 respectively. So although both were alive during the lifetime of their great grandmother Queen Victoria, neither had arms that might have required a label of 7. But note also that by the time the two princes were born their father, Prince George (later King George V) was already Duke of York with a label of three points. So the two infant princes would never have needed a label of 7 anyway!