Memory loss

I am starting to wonder if my older girls are suffering from memory loss. It seems like in the past few weeks they have forgotten every rule or guideline they have had to live with for the past 6-7 years. I am constantly saying " You know you are not supposed to do that!" " Dont you remember the rule?" I feel like I am having to re-teach them everything!! I guess it is the preteen thing, but seriously, retain something in your brain for petes sake!!