Settling the age-old debate: Do MILFs *have* to be actual mothers?

Although the original definition of the term very much implies moms-only, this dude makes some solid arguments that the definition should be expanded to generally maternal/more mature women as well. I'd certainly make the argument that Aunt Cass and Aunt May are both basically the mom in their respective stories, and I'm all for being inclusive to middle-aged hotties of all persuasions!