This is maybe why some step-parents really struggle with discipline. They may have successfully raised another family, and when they join a new family they think they can use the same discipline techniques that were effective with their other kids, but it often goes horribly wrong.
There might not be anything wrong with the actual techniques, it is just that it takes years to build relationships up to the point where step-children will readily accept discipline from their step-parent. It is usually wiser for them to step back and support the ‘bio-parent’ in their discipline; as well as that, they should concentrate on building his or her relationships with their step-kids.
The principle applies to all of us: the real key to good discipline is what you do when you are not actually disciplining: it’s the communication, the respect, the love and the structure that creates the backdrop for effective discipline.
Some parents have punished and penalised and taken things away from their kids… but they are still getting the same difficult and challenging behaviour. They probably need to take the kid on a camping trip or go and kick a soccer ball around for a while.
Rules without relationship leads to rebellion. You need to build up that credit balance of affection and relationship so the rules can actually have some traction. That is especially true if you want your rules to apply when you are not around to enforce them. You can get compliance through threats and fear, but don’t expect kids to follow them if there is no longer any risk of being caught!