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Ron L. Deal

I’ve been talking and writing about this for years. And every time it comes up parents and stepparents look at me as if I’m crazy—until it happens to them.

Craig talked to me at a conference: “I can’t believe my daughter and her stepbrother, Josh, are telling us they have romantic feelings for one another. Even though Josh doesn't live with us they have grown up knowing one another; my daughter was two and Josh was three when Carri and I married. How can this be? I guess they have already kissed at this point. What do we do?”


Brad and Gwen had been seriously dating for about a year when they discovered that her son and his daughter had a crush on each other. A friend told Gwen that the talk at school was that if Brad and Gwen got married, their children would be living in the same house—and they already liked each other.


Robert wrote to our ministry with a very heavy heart. “We are going through a storm and need some guidance. Marsha and I have been married for four years with four children and feel we have a healthy family situation. That’s why we cannot understand why this has happened. My son, Ian (age 17) and Marsha’s daughter, Monica (age 15) had sex last Sunday night. They have been like brother and sister throughout our marriage and now they have lost their virginity to one another. I’m just glad guilt took over and they confessed within a day. We have asked for help from our youth pastor and have talked with the kids about their decision, but we know this has changed our family forever. How could this have happened? We were proactive in teaching our children about healthy sexuality and God’s values. What do we do now?

Understanding the Vulnerability

First, let me say very clearly that internal stepfamily sexuality—between stepsiblings—is very rare. And yet, it does happen. Why?

In The Smart Stepfamily I devoted an entire section to discussing the dynamics surrounding intra-family sexuality in stepfamilies. Let me summarize those key points here:

  • No Natural Taboo. Biological siblings have a natural taboo against sexuality. It seems that “shared DNA” is a powerful deterrent to sexual attraction which is one significant reason incest is rare. Ask someone if they think of their biological siblings in sexual ways and they’ll say, “That’s gross!” Stepsiblings don’t have shared DNA and therefore, don’t have the natural taboo. This doesn’t necessarily open the door to sexuality, but it does unlock it.
  • The Command for Closeness. When two families come together there is an assumption that people will do just that—“bond together." This creates an unspoken expectation that stepsiblings will move toward one another. Displays of affection, warmth, and hugs of endearment are non-sexual ways of communicating this coming together. However, non-sexual touches can take on sexual implications, especially for teens whose psychological boundaries are not strong.
  • A Sexually Charged Environment. This occurs for a number of reasons. First, before the wedding children watch as their parent goes through a period of dating and developing romance. Children may coach their parent on how to act, talk, or what perfume to wear on a date. In addition, a child is often witness to the increasing physical affections and touches that couples share as romance deepens. One father shared how this impacted his children. "While dating I kissed my future bride in front of the house before saying good night. My youngest son poked his head around the corner and yelled, `Goooooo Daddy!'" Children can't help but witness these romantic affections.

    But romance doesn't stop there. A second reason for a sexually charged environment is what happens after the wedding. The first year of marriage is frequently speckled with romantic gestures and snuggling on the couch before bedtime. All of which communicates the message that "sexuality is alive and well in this household."

  • Developing Teenage Sexuality. Our society is obsessed with sex. It pervades the movies, music, and conversation of the average adolescent. Sex is everywhere—outside and “inside”. Changes in hormones and physical appearance inside a child’s body lead to many confusing thoughts and feelings for teenagers. It is imperative that parents present a godly view of sexuality—it’s purpose and promise—throughout adolescence. If parents begin early to discuss God's design for our bodies and sexuality, important conversations with confused adolescents will be easier. But whether easy or difficult, such conversations must take place.

These are just some of the dynamics that may contribute to romantic or sexual boundaries being crossed in a stepfamily. Therefore, it’s best for parents to be proactive in preventing such behavior; stepfamilies need to set behavioral boundaries that discourage intentional and unconscious sexual attractions.

Boundaries that Honor.

Set boundaries (rules governing behavior) that teach family members to honor one another. Respecting privacy and valuing the specialness of each family member is an important message for everyone to learn.

  • Set rules that honor privacy. It may feel totally unnecessary, but consider having a dress code. Teenagers, in particular, can overlook how their dress invites others to see them in sexual ways, or consider them a symbol of sexuality. Girls, for example, who sleep in their underwear and a long T-shirt may be comfortable walking around the house dressed for bed. Little do some girls realize how that arouses a natural curiosity within boys about their body shape. Boys can easily entertain thoughts that cross from non-sexual curiosities to sexual ones. To counter this possibility, set a dress code and explain why it is necessary.
  • Other rules you might implement include knocking before entering bedrooms and how persons will share the bathroom. Help your children work out a respectful system for shower schedules and sharing bathrooms.
  • Boundaries are particularly important when a stepsibling from another home moves into your home. Children and teens that have known each other for years, but never have lived together full time, need clear rules of conduct.
  • Be sure not to turn a blind eye to any signs that someone is uncomfortable. If you perceive a child withdrawing or showing signs of stress, calmly approach the child to investigate the situation. Error on the side of caution.
  • Have frank discussions with teens and pre-teens (separately) about sexual boundaries and healthy sexual attitudes. Setting rules that honor sexuality and privacy is sure to create opportunities for adults to speak with children and teens about sexuality. Take advantage of such opportunities to teach God's purpose for sexuality and the protection his statues provide. The message parents give children in stepfamilies is the same fundamental message any parent would give—it just applies to people both inside and outside the home. The message is this: your sexuality and the sexuality of others is a gift from God that is to be honored and protected. Healthy sexuality between two married people helps build their relationship to each other and God. Sexuality outside God's boundaries erodes relationships and creates a sin barrier between God and us.

    Unfortunately some parents rely on scare tactics to encourage sexual purity before marriage. In an effort to keep their children from having sexual thoughts or urges, they scare them with the consequences of premarital sex. I believe we should be honest with children and teens about the potential emotional and physical consequences of premarital sex. However, the scare method doesn't present sex as a gift from God to be honored. It turns it into a curse to be avoided. When children grow to be married adults, switching the messages in their brain to see sex as something to be embraced and pursued is often difficult. It is much better for parents to teach sex as a gift to be protected and honored. God's law that sex is kept until marriage is meant to protect us from harm and provide for our sexual pleasure in marriage. We can teach our children to protect one another's honor and their own so that the gift of sexuality can be enjoyed later in its proper marital context.

  • Talk about sexual attractions in a matter-of-fact manner. Having healthy and honest conversations about the sexual truths of life normalizes them for children. For example, explaining menstruation to a pre-adolescent girl or wet dreams to a boy before they occur prepares the child for the onset of such experiences. Preparing and normalizing such experiences is important because, in addition to teaching children proper hygiene, it gives the child a God-perspective on the event ("You're becoming a woman!").

    In the same way, acknowledging that sexual attractions between stepsiblings can occur normalizes them for the child. This is not to give permission to them, but to teach a proper perspective. The alternative is to say nothing and leave the child to determine the meaning of such an attraction (not a good idea), or to give negative messages that needlessly shame children ("How could you think something like that about her? That's disgusting.").

    Instead, a parent might say something like this to his son: "You know son, as we talk about sharing the bathroom with your stepsisters it occurs to me that some kids in a stepfamily like ours sometimes have passing sexual thoughts about their stepsiblings. If that ever happens to you, it doesn't mean you are bad or a disappointment to God. There will be lots of times in life that you have sexual thoughts or feelings toward other people, but it would be inappropriate for you to act on them or keep thinking about the person in that way. So if it happens, ask God to help you to stop thinking about your stepsibling in that way. And make sure you don't dishonor the other person by acting on the attraction or thoughts. If the thoughts keep happening and you get concerned about it, feel free to talk to me. I won't be angry. We'll find a way to handle it. Any questions?"

But What Do We Do Now?

The last section dealt with prevention. What do you do if stepsiblings have already been romantically or sexually involved with one another? Here are some suggestions to consider.

Each parent should take primary responsibility for their child. You will need to have many discussions with your children about what happened, how it happened, what they are feeling toward one another, and how you will manage the relationship in the future. Spend lots of time talking as a couple to make sure you have the same expectations for the children, then communicate them to your child. You can stand together as a team while doing so (I hope you can), but it’s usually best in high stress situations to let each biological parent be the point person to their child. This will not be a one-time conversation. Sexual sin has many emotional, psychological, spiritual, and familial consequences. You will be processing these consequences and life lessons for a long time.

What About Everyone Else? You will have to decide as a couple how to manage the rest of your family. Are there other siblings who are aware of the situation? I believe they should know at some point, but when? What developmental matters of the other children (e.g., age) should you consider? Will you tell extended family members? Why or why not? There is no universal answer to these question; each will have to be based on your circumstances.

Decide together what consequences to impose. Helping children learn from their decisions sometimes involves punishment. Decide together how you will respond to what has happened and follow-through. Be sure, however, to balance your discipline with reinforcing statements of love and assurance. Overreacting in anger and shaming a child without messages of acceptance can drive them further into sin.

Make sure physical boundaries are clear. If you haven’t been proactive in establishing a dress code or rules to manage physical boundaries (e.g., “knock before entering someone’s bedroom”) you must do so immediately. The emotional chaos and anxiety that will result from sexual lines being crossed will necessitate structure and clear boundaries for everyone. Try to avoid going into complete “control mode” as parents, but provide insulation where you can. This may mean that the children can’t be at home by themselves after school as before or other common sense boundaries. Try to remove temptations. Remember, sex doesn’t have a “reverse” gear, only “forward”. In other words, once kids have had sex, doing so again becomes a lot easier.

The most awkward boundary to discuss is future physical affections. As family members stepsiblings share hugs, hold hands during family prayers, and say “I love you.” Once celebrated in the home, these common family affections will now be considered suspect. Can the children go back to a time of innocence? They cannot. They need to be able to express appropriate affection, yet doing so may be confusing. In addition, how will you know when your fears are exaggerating the circumstances? All of these issues will need to be discussed and sorted-out over time.

And what about affections between other family members? In one family after two teens engaged in sexual touch it affected the couple’s marriage. Not wanting to encourage repeated behavior by the children, the wife became fearful of showing her husband affection both publically and privately. A temporary response such as this is understandable, but over time this has the potential for real harm in a marriage. Guard yourselves from becoming victims of your anxiety.

Have “What if” Conversations. These are aimed at changing behavior in the future.

  • “What if you two find yourself at home alone. How will you handle it?”
  • “What if you feel attracted to them again. What will you do?”
  • “What if someone brings this up and you feel embarrassed. How will you act?”
  • “What if you feel pressured by your stepbrother/sister?”

The possible conversations are endless. In effect, this type of question helps a child take responsibility for themselves and develops an action plan for the future. Some parents are tempted to tell a child what to do and how they will feel. In highly emotionally charged situations like this, doing so—especially with teenagers—usually backfires. Help them think it through with you and come up with their own strategies. Your job is to coach their thinking process toward maturity.

Engage in “What Have You Learned About Yourself?” Conversations. Again, these conversations are aimed at helping the child grow through this experience. You wish it didn’t happen, but it did. Help them learn something about themselves.

  • “What made you vulnerable to this situation?”
  • “What were you thinking when you began undressing?”
  • “In what ways did you rationalize or justify your behavior?”
  • “You know that being stepsiblings makes this very complicated for our family. How did you dismiss that when you pursued the relationship?”
  • “How will you manage your vulnerabilities in the future?”
Still Family

Without question, sex between stepsiblings is a family tragedy, but you’re still family. Applying firm but loving consequences and boundaries, and much needed grace and forgiveness to your circumstances will begin a healing process> for your family. Things will not ever be the same—there will be much heartache, but in time there may also be something to be grateful for. But not if you give up, shut down, or cut yourself off from each other. Seek the Lord’s help, get outside support from a trusted counselor or pastor, and press on.


Ron L. Deal is Founder & President of Smart Stepfamilies™ and Director of FamilyLife Blended® for FamilyLife®. He is a bestselling author, highly sought-after speaker, and therapist specializing in marriage enrichment and blended family education. Learn more here.