The Dunwich Horror (Lavinia and one of the twins) by Viant-T (www.wilburwhateley.tumblr.com)

Lavinia Whateley may or may not have been the result of inbreeding among the Whateley’s, since albinism is not solely the outcome of inbreeding; more than likely such deviant activities were involved in the birth of the Whateley twins.  More specifically, there is evidence to suggest that Old Wizard Whateley “contributed” toward the conception of the twins.  This evidence is the fact that when the appearance of Wilbur’s brother is revealed, it is noted that it has “a half-shaped man’s face on top of it, an’ it looked like Wizard Whateley’s, only it was yards an’ yards acrost…” (Lovecraft’s “The Dunwich Horror”).  Indeed, even before this revelation, it was suggested that Wilbur was the product of inbreeding (Sex and the Cthulhu Mythos by Bobby Derie).

Based on how the twins differed in appearance Wilbur and his brother…