blenders are for families too

Don't be fooled by the title of this post.  I'm not some morbid psycho.  Give me a chance to explain myself.  Sometimes in life, well, life happens and families separate.  And then sometimes mom gets remarried, or dad gets remarried, or they both do.  Sometimes the new spouse comes with a bit of baggage we call kids, and would you look at that, we have a blended family.  A yours, mine, and ours kind of situation.  Statistics show that it takes about 2 years for anything thing in a blended family to feel normal.  And even then, the step-parent will more often than not just seem like an aunt/uncle figure to the step-child.  The birth parent will be the one dishing out any heavy discipline.  Consequently the children could get smart and use this to their advantage.  A sort of abuse of power to get just what they want.  What do you think?  I've seen it happen in the movies, is real life the same?