Hello there babyumi, how are you? Welcome to this site.

Well one thing I know is that many step-parents often try to discipline children too soon. The children then, especially if they're teenagers, obviously react negatively to this, and think like "He or she is not my real dad or mum, so I don't feel he or she has got the right to tell me to do such or such thing.". It's advisable to try to know and build relationships with the child first before "applying" any authority on him or her.

First of all, it's very hard for a child to accept that his mum and his dad will no more live together. Children usually want their parents to live together forever and someone intruding his parents life can be an ennemy for him. He may be really angry against the stepparent and think he's the one guilty for his parents' separation. Some kids never accept the separation of their parents

__________________

I destroy everything around me
just like a tornado

Yea, and rushing the children into the acceptance of their new life could have the exact opposite effect of what is expected. Having new ways of life, new schools, new friends...stepbrothers and sisters with whom to share new rooms, new intersets and activities. All this pressure can push the child to get withdrawn on him/herself, or trigger off arguments, get into tantrums.