1. Lydia, the mother, complains to her husband George that she no longer feels needed--the house cooks, cleans, and now the nursery entertains/plays with her children. She senses from the beginning that the nursery is taking her children away from her and feels that she has to compete with technology for Peter and Wendy's affection.
2. When George begins to see the danger of the nursery, he tells Peter and Wendy not to imagine Africa anymore. Both children not only lie to him, telling him that there is no Africa in the nursery, but Peter orders Wendy about, and she obeys him but does not obey her father when he tells her to come back to him. At this point, it is more than obvious that the children possess the authority in the virtual home. They are more tech savvy, and they know that they hold the upperhand in that area over their parents.
3. Most significantly, the virtual home has robbed the children of any sincere love for their parents. Because the home does everything for them and their parents, they do not have to spend any time together. Everything is virtual to the children; so it is possible that they cannot distinguish between their virtual nursery world and the real world--this is the only explanation for their cold reaction to trapping their parents inside the nursery where they are eaten by the lions.
While Bradbury's story is extreme, it is eerily similar to some of the problems of today's American families--many parents sit at the dinner table (if they even do that) with their children, and each family member texts or watches TV throughout the meal. I recently heard one parent say that she really enjoys Facebook because that's how she communicates with her middle school-age children--is that really considered communication between children and their parents, especially when they live in the same house? Thus, even though Bradbury's story was published decades ago, perhaps he was not too far off when it comes to how dependent upon technology we will allow ourselves to become.