Not sure where you got this info, but I'm finding it VERY hard to believe PS had a fb account. Perhaps you are confusing SS & PS checking in? As someone who was good friends with AS & I was also/still am her fb friend. PS was NEVER tagged in any of her posts (but other family members were). Please note I am talking about her private posts which only friends of AS's can see, not the public. Moreover, I know of ZERO classmates of PS who have FB accounts. Also, please know AS & SS were probably the MOST protective parents in the class in already very protective community of parents... case in point, last fall a classmate (whose parents knew AS & PS very well) had his birthday party at their house on the Eastern Shore (of Md)... just a handful of boys were invited and stayed over the weekend with the family, AS & SS did not let PS go for the sleepover part but instead accompanied PS for the day on the eastern shore. They were extremely careful about who he spent time with and what he was exposed to. Again I state that perhaps you were thinking of SS not PS for checking in.
Finally, as I stated earlier, as a longtime parent of a child who was in PS's class for many years, I can also say with certainty that nearly all of PS's classmates do NOT have cell phones. (Interestingly, most 5th graders at PS school do have cell phones, but only 1 or 2 4th graders).