OK, I am back. difficult children stepmom became someone she could talk to. difficult child had me and her dad harping on her all the time (at least that is what it seemed like to difficult child). But, stepmom did not at first, so difficult child confided in her and they became friends. Only bio parents did the disciplining.
The more difficult child showed her true colors the less friendly it was - can't say I blame stepmom. My difficult child is not someone I would pick to be friends with.
Make sure the rules are the same for all kids in the house and be very specific what changes to rules are made due to age differences. Make the consequences very clear as well. When you write them out think about what could possibly be twisted around in any way - difficult child will find the loophole! LOL!