Long time listener, first time poster.
I've come up with a way to skirt the incest issue for June, using her theory that these are demonic creatures whose biology is too different from our own to have a true Mother/Son relationship.
Sleepwalkers are like Gremlins. Consider Stripe from first Gremlins film. When he falls into the fountain at the end he begins to create more Gremlins from his back. Now, can Stripe really be considered the "mother" of those Gremlins in a traditional sense? And if they had the ability to bone (besides being horrifying) could it be considered incest as we understand it?
So, I propose that whenever they feed off on enough virginal energy the Sleepwalkers spontaneously create newer Sleepwalkers. Only problem? Not enough virgins left who are old enough to harvest (I'm making up this rule to explain why there aren't billions of them everywhere). Why would they refer to each other as mother and son? Because it's hilarious that humans don't understand how special they are. Just like June said.
Unfortunately for June I have almost no proof for this scenario, except this: Sleepwalkers are know to be "Loving to feed, feeding to breed." Feeding to breed? Almost like... A mother fucking Gremlin.
