Wayne L. Misner
The combinations of the mixed family unit come in many varieties: her kid(s), his kid(s), and their kid(s) together. The ages of the kids and the stages they are going though also create different problems at different times during the relationships. Disciplinary methods create a very large problem. Both partners will have their own style of discipline and the consequences to be paid when your rules are not followed. Even the consequences you come up with might change depending upon your mood or based on how you felt that day or at that particular moment.
The rules and consequences are different for each age. An example for your thirteen-year-old son is that on school nights the rule is that he must be home by 10:00 p.m. The consequence if he were late (by fifteen minutes) would be grounding the next night. When both of you agree what the rules and the consequences are, they should be typed. A meeting with each child to go over, in detail, every rule and consequence should be held. The child must understand each one thoroughly and then sign at the bottom of the list making a contract between all of you. This signing makes the contract appear more binding.
I cannot stress how important it is that both of you present a united front to the children on the rules. If you do not, the child will play both of you against each other, subconsciously or not. And stepparents know that when they enforce rules, kids resent an outsider coming into their space and feel, more acutely, the loss of their parent. Without the contract, the child may challenge the stepfather or stepmother with "you're not my father" or "you're not my mother." The kids will especially fight the rules if they believe the non-parent set the rule. You both must be united in this effort.
Another area which will help eliminate potential problems is the handling of an allowance. The allowance should be in two pieces, a flat amount and an incentive scale allowance. The flat amount is given the same time and day every week with no strings attached. (The allowance should be paid without the child asking for it.) They do not have to do housework or homework to earn this portion. This allowance is given to teach the child the meaning of money. If they spend the allowance the first day, then they learn to wait for next week to have money again. If they want something which costs more than the weekly allowance, they must save some money over time to buy the item wanted. The amount of the allowance should be based on the age of the child; the older the child, the larger the allowance.
The second piece of the allowance is connected to chores. A figure is established for each chore, i.e., wash dishes, take garbage out, mow lawn, wash car(s) etc. Now when they want something, the incentive is not to take just the regular allowance but add to it the incentive allowance by doing extra chores during the week. You want to encourage the extra chores. This method is building the foundation for adulthood. When adults work harder and produce more, they normally get paid more.
One caution when applying a consequence for a broken rule: do not "cut off your own nose to spite your face." If the thirteen year old boy stayed out on a school night past the ten o'clock curfew and the consequence is being grounded the next day, before grounding see what is happening the next day. If he had been scheduled to go to a religious retreat, you do not want to ground him that day. Any time something is happening to help build his character or enables him to mature, let him participate. But he should be grounded the day after the event.