Again, an entertaining episode - the one about The Veld by Ray Bradbury. It's interesting how easily the thoughts about the 'mechanization and entertainization' of the house(hold) in the fifties (tv, vacuum cleaner...) and the worries and effects they could cause, can be translated in the modern discussions about the effects of the social media and digital world on our social system. But that's Bradbury. And I like his concern for children and parenting: a theme that's not often handled in literature, in my opinion (although there's Peter Pan and The Lord of the Flies...).
When I read this story, I also had this question in mind: was it a real lion that killed the parents? I also thought it strange if it was a real one (VR is not real). But if it was the girl, why didn't they see the girl? I think maybe the answer lies in the fact that this VR was induced by the mind, so maybe the images (and sounds and smells) are not received by the sense organs, but immediately by the brain itself. If that's the case, the girl could have 'disguised' herself as a lion, after messing around with the nursery-system (maybe a bit like 1 'if optical input=girl then optical output=lion'; 2. add lion to Veld).
But after all, I don't think the discussion about the lion/girl is not the most important one in this tale (although it's fun to think about) :-)