I think manipulation is something you learn when you are young. You try something and if it works you make it part of your personality for all times. I will give you and example. When my niece was little she used to play with my neighbors granddaughters. The were lovely well behaved little girls and I loved having them all around. On the days I babysat my niece I would feed her supper. Most nights I would just make enough for the two of us as I am on a fixed income and can not afford to waist food. My niece started asking if her little friends could eat with us. This would not have been a problem HAD SHE LET ME KNOW EARLIER that she wanted them to stay so I could make more. She would wait till I told her to get ready to eat before she would ask RIGHT IN FRONT OF THE LITTLE GIRLS. So if I were to say no it would make me look like the meanie. More then once I had to try to stretch supper for 2 into supper for 4 at the last minute.
I took my niece aside and said to her : I hate when you ask in front of them because sometimes I did not make enough for 4, and if I say no then I look bad to you all, but it could just be I did not have enough made for 4. I told her, from now on if you want them to stay DO NOT ASK ME IN FRONT OF THEM! Take me off to the side and ask me and if I have enough made they can stay, but if I tell you no you do not even ask in front of them. She asked me in front of them again after being told not to. I let it go while they were here , but when they left she and I had another talk. I reminded her what I had said about asking in front of them, and this time I added THE NEXT TIME YOU ASK IN FRONT OF THEM EVEN IF I HAVE ENOUGH THE ANSWER WILL BE NO BECAUSE YOU DID NOT DO IT THE WAY I TOLD YOU TO. A few days went by and danged if she did not do it again in front of them. I looked at her and said WHAT DID I TELL YOU? Then I looked at the other little girls and explained it all to them like I did my niece. These are very intelligent well behaved little girls and they totally understood it was nothing against them, but I wanted my niece to do things a certain way and she had disobeyed me. Then I turned back to my niece and said I told you to stop asking in front of them and you did not do it. I also told you next time you did it even if I had made enough the answer would be NO! I could not believe what my niece said next. After all that she actually had to nerve to say again IN FRONT OF THEM well can they stay? I looked her right in the eye and said NO I TOLD YOU IF YOU ASKED IN FRONT OF THEM THE ANSWER WOULD BE NO AND YOU DID SO NO IS THE ANSWER. I then turned to the other girls and said I am sorry if she had asked me like I told her to you could have stayed, because I did have enough made today. But because she can not learn how to do it right she has forced me to make my point. IT WORKED. That was the last time she asked me in front of anyone she learned to ask me on the side.
Had I allowed her to get away with this thing of asking me in front of people to get what she wanted she would have kept doing it. I know she had been doing it with her parents and getting away with it, because when I told her mom what I did she said she does that to me all the time. I told her mom well she is done doing it to me. I refuse to be manipulated that way especially by a child. The ironic thing is I have noticed some adults will do the same thing. lol If they think you are going to say no about something or have a problem with something they are about to do they will let you know about it in front of other people thinking you will do what they want then. And yes sometimes it will work depending on the circumstances, but if they think they are fooling me they are nuts lol I know exactly why they do things the way they do.
So the moral to this story is if you do not want your children to grow up to be manipulators do not let them get away with it when they are kids. Bad behavior is soooooooooooooooo much easier to stop in a child then in adult. However it is not impossible to stop in an adult if you can get them to see what they are really doing. *smiles I stopped my brother from picking on me after nearly 50 years of him doing it. You have to be creative to correct bad behavior in adults lol so fix it while they are little, and save everyone a lot of headaches.