The role of a stepparent in a stepchild's life can be very different depending on what circumstances surround the relationship between stepparent and stepchild.
If You or Your Co-Parent Is Not Remarried but a New Partner Is Involved
If you and your new partner are not married, there is no stepparent relationship between your partner and your children, and that means you should never let that partner assume he or she should have any say in how or when children are disciplined. You can try to make the case that your new partner is an older person to your children and therefore should be respected—and of course this is true. Children should respect adults, but a stepparent is a very special type of adult—one who is related to you, the biological parent.
Let's say you are the biological mother of a child and you are living with someone, and your child says something very disrespectful to you. If your boyfriend steps in and sends your child to her room, it is a very bad move. You are the one who should be disciplining in this situation. Your boyfriend can be as offended as anyone in this circumstance would be, but he should not step in or hand out punishments and should never, ever spank or hit your child. In nonmarital arrangements, the biological parent needs to be the disciplinarian.
Whether you are a mother or a father, you always want to control for the possibility that your current arrangement might ultimately not work out. If you permit your partner to walk away from the relationship being the one who disciplines the children, you might have a very difficult time establishing yourself as the primary person of influence over the children.
Similarly, if your partner turns out to be a bad person, and your children knew it all the while, if you had given that person too much power in your household you might see your children upset at you for not ending your relationship sooner or exposing the children to someone they might not have liked in the first instance.
If You or Your Co-Parent Is Remarried
In the case of remarriage, is the child required to listen to and mind the stepparent as a biological parent? That depends on a lot of factors, but generally speaking the stepparent should play a secondary role in matters of discipline and influence, even if you are convinced that he or she is a better parent to your child than the biological parent.
If your child has little or no access to his other "real" parent, and the stepparent is the only parent the child has ever known, this doesn't necessarily make life any easier for you or the stepparent. It can be just as difficult for the stepparent to compete with the idealized parent your child imagines his other biological parent to be. In short, there is almost no situation that will prevent your child from firing the phrase "I don't have to listen to you—you're not my mother [father]" to his stepparent.
Between the totally absent biological parent and the totally present biological parent are a lot of different configurations. Life is always better when everyone can get along. When stepmother and biological mother have an understanding with one another, and when stepfather and biological father have an understanding, those are good situations. When there is competition, hatred and loyalty issues can get significantly more complicated. When that happens, the stepparent should default to being a background influence on the child.
Quick Tip
Unless the biological parent is completely out of the picture from a very young age, boyfriends and girlfriends who are not stepparents (and even, to some extent, stepparents) should always play a much lesser role in disciplining children.
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