Board Thread:Suggestions forum/@comment-91.214.88.227-20191105181942/@comment-34030170-20191107002244

And even assuming Ungoliant was a Maia, that doesn't mean that Shelob was, too. Lúthien's not a Maia, despite being the daughter of one.

Furthermore, even if both Ungoliant and Shelob were Maiar, they'd almost definitely be stuck in their spider forms, from all the evil, devouring, and mating they do.

Rant over.