Morwen, she is red in her face as if from a sunburn, but actually blushed. In Lord Burgess' version, she pretends to be sunburned to hide her frustration about her lost lover. The "moonshine" version, obviously older, is a bit enigmatic, but it seems to amount to the same: things happened in the dark night that made C'delia blush the next day.

We can imagine her to be of bright complexion, her first name (invented by William Shakespeare) indicates a family proud of their European culture. Before you ask: unfortunately I do not know any more about the story, in neither version.