Yeah yeah, duly fixed. Care to address the substance of my questions and argument?
Which parent? - Both Parents
Step-Parent? - Negative, only Biological parents should be the disciplinarian
After 18? - I agree there is a limit as to when you should stop spanking, it is really hard to paint a general number on, I said 18 because after that point, they are a legal adult themselves, it is indeed hard to paint a magical number.
You may think, generally speaking, spanking should not occur on a 16 year old, but every situation is unique, and it is hard to say that it is wrong for every situation. My sister is 15, and believe you me she definitely needs a whipping!