Behavior. Nature or Nurture?

Why do people behave the way the do? I know that question has been on the minds of people through the ages and we as humans will probably never stop thinking about it. Even as we discover what parts of the brain cause behaviors, we still mostly don't know why. My thoughts are stirred tonight because of another blogger/my own children and my siblings.

 1. My very bright and beautiful daughter seems to be going through normal stages of childhood. She's 4 now and we went through the terrible twos followed by a stage of amazingly good behavior. Now we've hit a stage where she's trying to throw tantrums again. I puzzle over why she's doing this. My best guess is that she's now the oldest child at daycare now and since she's surrounded by younger children, she is acting like them. ?? I really don't know. She is good at manipulating situations and turning things around to her favor. I assume that it doesn't help that she has a grandparent on both sides that gives her every thing she wants and never utters the word 'no'. At home, she doesn't listen very well anymore. I will ask her to stop and she's "just playing" but she continues even after I've asked again, which leads to time out or a spanking and then she starts slapping things like the couch or a toy. Why has she started doing this? Not a clue. It makes me angry and worried for her. I hope it's just a stage and she grows out of it soon.

On the other hand, my son seems to be very well mannered and behaved. He's skipped the terrible two's so far and he's very helpful around the house. He will clean with me, exercise with me, and even put his coat where it goes after ripping it off. When he was 18 months old he would open Hershey Kisses over the trash can so he wouldn't make a mess. He says excuse me and thank you and when I scold him he gets upset but accepts it. He seems very aware of what he did and why it was wrong. He's nice to his sister and is constantly sharing. She takes full advantage of this though and that bothers me. I think I'll be able to talk him though anything and he'll look at every aspect of it and understand.

I mentioned another blogger because she's having issues with one of her younger children and she's not sure what to do because she feels that she might have made a mistake with one of her older children. I'm a strong believer in learning from everyone's mistakes, so I really like to read her thoughts on the situation. I personally feel like she must be an amazing parent and that leads me to believe that sometimes, people are who they are no matter what you do. That's scary too, because that means that there's no way to fix the world. If that's true, then good parenting won't do it and it seems like the most promising thing to me. She's trying to let her children be themselves, which I think is important too.
My problem is that I don't know where the balance is. Where do you draw the line of letting your child be themselves without letting them run your world? Can we really make change their behavior without changing them? I'm not really sure. I know I definitely want my children to grow up to be respectful and educated.

 2. My siblings. I don't even want to claim them anymore. I rarely think about my oldest and I wish my middle one would learn something, anything! I come from a normal middle class family. My parents were never divorced and though they fought sometimes, they usually got along very well. We had money to buy things and my parents took us places. They never abused us, never chose cigarettes or alcohol over us, and never let us go hungry. They are extremely stable people. They haven't always done the right thing, but they took care of us.

They ended up with 3 children: My 2 older brothers and myself. My oldest brother started rebelling around the age of 14. I was 1 then. He threw angry fits, nothing was ever fair, and he never followed the rules. It wasn't as noticeable until he turned 16. My parents bought him a truck and didn't even make him get a job. I think that was their biggest mistake. He didn't have any responsibility. He still shouldn't have turned out the way he did. He has 4 kids that we know of. He never sees any of them and doesn't care about them at all. He beats on women. He drinks. He's a druggie. He's violent. He's also very friendly and a good story teller. If his good side showed all the time, he'd be an amazing person. It only shows in the beginning though. He goes through a pattern. He manipulates people with his friendliness and then becomes violent if they refuse and tries to scare them into doing things. He's even threatened my parents and been in fights with my dad. He's homeless and jumps around from house to house mooching off of any one he can: usually druggies. He's not allowed to see my parents right now and I think he's actually in jail in OKC. I'm happiest with him when he's in jail. I know here he is, he's always on his best behavior there so he can get out, and he has a roof over his head and food to eat. He's still a loser though. He's been helped time and time again and I resent him because he stole a lot of my childhood. My parents were so focused on fixing him, that it took time away from me.

My middle brother used to be a little smarter. Now he seems to be beginning the same road. He has two daughters that he pretended to care about. He gives them a roof and food. That's about it. They go somewhere every weekend to get away from home. He doesn't abuse them or anything, but he's not a good father. If I had room, I would take them home with me permanently. They bide their time until they can leave and I don't blame them. I think they will be ok. I try and educate them with my personal life skills and they seem to soak it up and admire me.

I am the 3rd child: The baby. I am responsible. I've never done a single drug or smoked anything in my life. I've kissed one boy. I married him. Yes I've lied from time to time and I did try alcohol and will drink wine from time to time. That's ok though. I  take care of my children and spend time with them. I am educated and have a good job. How did we all come from the same family? This is where I come full circle. My parents disciplined them. Helped them. Were good parents. I turned out as a productive adult. They didn't. What is so different? Is it just who they are and it can't be changed or helped? Why would it be that way? Did peer pressure affect them more than my parents? Is it a personality type? I don't know. I hope it's not any of those things. I hope I can at least have a little control over who my children will be and what skills they have and choose to use.