Here we go again, from the same people who brought you plural third person pronouns as substitutes for third person singular (gasp!) masculine nouns.
I used to teach Japanese business executives English in Tokyo. I used to wonder what went through their minds when they read wrenchingly illogical American convolutions such as: "If ANYONE needs to use the men's room, THEY can find it at the end of the hall." And now we have the iniquitous folly of "Parent One" and "Parent Two." While they're at it, why not add "Three" and "Four"? And replace "Son" and "Daughter" with "Child One" and "Child Two"?
Would anyone like to hazard a guess what's really behind this desire to neuter language? And please don't anyone be so boorish as to say "the civil rights of gays"!