Kids do what parents do, and what parents allow them to do. Allowing X hours daily gaming/screens is already bad parenting (depending on age but we talk about kids here), like it or not ask psychologists. At the end its just same genes & upbringing from the same genes (or failure to do so and ie nanny picks up).

Everything else is just an empty blah. Every single time there is unruly kid, I look at parental behaviors and its pretty obvious. Reverse is also true - every properly caring involved parent has much better behaving kid(s) around.