I should probably write a glossary of my deliberately odd terminology and pin it to my profile. The "Mother Thing" is what I call my mother for purposes of this blog. She was the one who suggested I read Robert A. Heinlein's juvenile science fiction novel Have Space Suit, Will Travel when I started looking into science fiction back during my preteen years. In that book, there is an alien which the protagonists call the "mother thing" because it has a motherly personality.