Sibling Rivalry: Definition & What You Need To Know

What Is Sibling Rivalry?

Sibling rivalry is a remarkably common phenomenon in families that consist of more than one child. It is the occurrence of jealousy, competition, and/or animosity that can occur between siblings. While families may experience it in different levels of severity, it is bound to show up at some time in some way.

Sibling rivalry doesn’t have to be detrimental. In fact, it serves a developmental purpose. Individuals who grow up with siblings have a rich opportunity to learn conflict resolution, boundaries, self-advocacy and relational wellness. They also learn what makes them unique, what matters to them and their self-worth.

Some examples of sibling rivalry presenting include:

• Verbal or physical fighting
• Jealousy
• Name calling
• Teasing
• Sabotage
• Chronic comparison
• Competing for respect

The differences between normal and unhealthy sibling rivalry usually show up in frequency, power balance, and how children recover:

What Is The Psychology Around Sibling Rivalry?

Rivalry amongst siblings has been a growing interest for researchers of family structures, interpersonal relationships and mental health. In a 2015 study in Evolutionary Psychological Science, researchers Catherine Salmon and Jessica Hehman summarized the most common sources of sibling conflict: “Investigations of proximate explanations have found the most common sources of sibling conflict to involve issues of relative power, self-interest (e.g., sharing of personal items), violation of rules (e.g., perceived immaturity and inappropriate behavior), and interests outside the family.”¹ Dysfunctional sibling dynamics typically reflect marital or caregiver issues. Children often mimic the types of interpersonal habits and dynamics that they see in their parents and/or act out behaviorally to process the unaddressed tension in the home. Psychologists have studied this dynamic for over a century; Alfred Adler’s birth order theory framed sibling rivalry as a competition for significance within the family, and it remains a common lens for understanding these conflicts.

Any situation where siblings threaten one’s sense of safety and belonging will lead to some level of dysregulation, so the more often this phenomenon happens and the less it is addressed, the deeper the rivalry will be rooted. When a person internalizes deep rooted sibling rivalry, even seemingly neutral interactions can feel threatening and animosity becomes more common.

What Age Is Sibling Rivalry the Worst?

Unfortunately, there is no specific age that sibling rivalry peaks. Rather, it takes different forms depending on age. Young children may feel more consumed by sibling rivalry, especially as it relates to competing for parental affection and attention. As children get older, sibling rivalry can be more nuanced and subconscious, with jealousy and chronic comparison being the more prominent presentations.

What Causes Sibling Rivalry?

Sibling rivalry is most often caused by competition for parental attention, favoritism, major family changes, close age gaps, and a lack of conflict resolution skills, and it deepens when these issues go unaddressed or dismissed. Here are some widely identified causes of sibling rivalry:

Major Life Changes

Major life changes such as the birth of a new child into the family, divorce, death, blending of families through a new marriage or relationship, a big move, significant illness, trauma or other change can exacerbate the emotional resources of the family caregiver(s) and create a sense of dysregulation in the family structure. This dysregulation can increase underlying causes of sibling rivalry or create new ones.

When a family experiences a major shift, the sense of safety and predictability is compromised. Sibling rivalry stems from competition over resources, so this heightened state of hypervigilance can make siblings more on edge and less trusting of one another, which is a surefire recipe for conflict.

Ages and Stages

Sibling rivalry takes different forms throughout the lifespan. At a young age, it looks more like a competition for parental attention, jealousy towards a new baby sibling, and difficulties in sharing. As children get older, sibling rivalry commonly centers on comparison and sense of belonging. When children begin to figure out their identity, they look to their siblings to help provide an example. Into adulthood, the comparison increases in terms of how success is measured in a family culture, and in accomplishments. There is also potential for rivalry in estate planning, inheritance, and sharing of responsibilities regarding aging parents or other family obligations.

Jealousy

Siblings, especially those close in age and those of the same gender identity, are more prone to comparison which often manifests into feelings of jealousy. Disparities in sibling achievements and perceived successes, reputation amongst family and feelings of favoritism can cause sibling rivalry to be exacerbated. It is a universal human longing to feel accepted, loved and celebrated by your caregivers, and feeling like your sibling(s) are receiving that in higher quantities than you can enact a primal response of feeling threatened.

Individuality

Particularly in late childhood through adolescence, identity development and a yearning for belonging and individuality can cause tension within the family structure, especially in dynamics where favoritism exists and comparison is a common phenomenon. When there is disapproval towards the way a sibling is developing, or if a sibling breaks away from a family identity or value, it can create a culture of outcasting and animosity.

Lack of Conflict Resolution Skills

One of the most influential causes of sibling rivalry, which is also one of the most accessible ways to mitigate the issue, is lack of conflict resolution skills. So much of our early social development comes from our sibling relationships, and using conflict as an opportunity to teach mediation and resolution skills is incredibly valuable not only in strengthening the sibling bond, but providing them with tools to have healthier relationships throughout their lives.

Conflict is inevitable, and children rely on their caregivers to show them how to navigate it. Mediating conflicts, teaching explicit skills and providing sentence prompts, examples and modeling are all great ways to teach conflict resolution skills which will increase their mental and emotional health.

Family Dynamics

Some examples of family dynamics that can contribute to sibling rivalry are blended families, unplanned children, parental separation and mental health or addiction struggles. Situations where people have to navigate change and uncertainty as well as feel a level of scarcity in terms of parental attention or shared resources can lead to resentment and rivalry.

Blended families, adoption and birth of a child are the more commonly identified family dynamics that lead to sibling rivalry, as adjusting to a new sibling can be a very complex situation to navigate. Consistent, open and honest communication as a family through these transitions is critical in mitigating any precursors to sibling rivalry.

Lack of Structure

Homes that do not have set routines, expectations and accountability structures do not lead to less conflict, they lead to more anxious children. When there is minimal predictability and boundaries, conflict and rivalry are much more common because there are little systems in place to control it and emotions are often heightened.

Disparity in Care Needs

In families where one sibling has higher care needs, whether from a medical diagnosis, illness, disability or other condition, there often presents a significant disparity in the attention and care each sibling receives. This is especially true when the condition is chronic or lifelong and requires both mental and emotional resources from the family as well as financial. It can also be exacerbated by the request or need for the sibling to partake in the care needs.

What Are Examples of Sibling Rivalry?

Common examples of sibling rivalry include favoritism (real or perceived), constant comparison, competition over achievements, step-sibling conflict, inheritance disputes, and, at the extreme end, bullying or abuse. Though rivalry can display itself in a whole host of ways, all presentations are rooted in either jealousy, feelings of inadequacy, resentment, or some combination of the three.

How Do You Deal With Sibling Rivalry? 12 Tips for Parents

The key to preventing sibling rivalry from becoming an incredibly impactful and harmful dynamic is early and consistent intervention. Taking sibling rivalry seriously and addressing its root causes is important in maintaining a harmonious, respectful home and making sure each family member feels celebrated, valued, and understood.

While it is important to allow children to have the space to navigate conflict on their own and not turn to a parent for every disagreement, taking the time to coach them through conflict and teach resolution skills is an investment that will pay off significantly for years to come. Adele Faber and Elaine Mazlish’s classic book Siblings Without Rivalry popularized many of these coaching strategies for parents.

Things to do when sibling rivalry happens include:

• Call a time-out: When people are escalated, nothing productive happens. Teaching your children how to call a time-out and how to respect someone else’s time-out is a conflict resolution skill that will benefit them for years to come.
• Make sure each party is heard: When coaching siblings through conflict, it is not only important to give each party a chance to express themselves fully, but also to make sure the other sibling(s) hears and understands each point of view. Having your children repeat back what they heard or summarize it allows each party to feel like their voice matters and also helps them develop better listening skills.
• Support the use of I-Statements: Giving your children sentence structures such as “I feel ___ when you ____, I need _____” teaches concrete strategies to prevent conflict before it begins and have better communication and empathy.
• Find a take-away: Teach your children that conflict can be productive and help them find the lesson, take-away, or growth point from whatever the issue may be.
• Provide an out: Offering siblings a redirection gives them a chance to diffuse the tension and show them how to move forward. Suggesting an activity, action, or way to move past the conflict can alleviate feelings of stuckness and resentment.
• Restore the peace: Ensuring that the bond is restored in some way, perhaps with time, is important in maintaining the integrity of the relationship. Having the siblings remind each other of things they like about each other, something they have in common, or discussing a fond mutual memory can help restore a positive environment and help siblings stay grounded in their family bond.

Some tips for handling sibling rivalry fights:

1. Avoid taking sides: Sibling rivalry is often about parental approval. Ensuring that you are neutral in times of conflict can help all parties feel valued and equal.
2. Get curious: All conflict has an underlying unmet need. Before you get furious, get curious about what isn’t being met.
3. Be fair, not equal: Different people need different things. When children feel secure that their needs will be met, and learn that their needs may be met differently than a sibling’s, they become less focused on keeping score with one another.
4. Address the root cause: If you notice patterns and consistencies in sibling conflict and rivalry, addressing the root cause will help prevent future conflict as well as strengthen each sibling’s mental health and relationship.
5. Stay in control: During times of sibling conflict, it is important to stay calm, composed and in control. Siblings often look to a parent for guidance in these situations and it is important to model emotion regulation during tense times.
6. Praise in public and discipline in private: Maintaining neutrality as a parent often feels impossible and a never-ending balancing act. Being as intentional as possible about disciplining children individually and privately and speaking highly of them in front of others in an equal manner helps in preventing a “problem child” or “golden child” narrative and helps to prevent the development of deep shame.
7. Model conflict resolution: This is especially impactful if you yourself have siblings. Talk about your relationship with them, how you manage conflict, and model what you want your children to do.
8. Celebrate uniqueness: When children feel secure in knowing what makes them unique and see that their parents understand their individual strengths, competition and jealousy become less enticing.
9. Be intentional about bonding time: Finding individual bonding opportunities with each child, as well as whole-family quality time and opportunities for sibling pairs to bond, will help each family member feel celebrated and decrease feelings of animosity.
10. Have clear family rules: Boundaries and clear expectations regarding how we speak to one another, treat each other, and navigate conflict are important in maintaining a respectful and value-driven home.
11. Be proactive: Paying attention to what happens prior to conflict and taking steps to mitigate those situations before they become an issue can go a long way in maintaining a harmonious home.
12. Avoid the “coop-up”: Within reason, keeping busy doing enjoyable activities keeps everyone feeling good, with less time and energy for conflict.

How Can Parents Prevent Sibling Rivalry?

Regular, intentional family bonding is one of the strongest protections against sibling rivalry. Being intentional about family bonding opportunities as a whole, as well as between sibling pairs, parent-child pairs, and other small groups within the family, is important. The key to these bonding opportunities is equity. While each member of the family does not necessarily need the same amount or type of bonding time, ensuring that everyone’s need for belonging is met and individualizing that approach makes sure that everyone feels like an important member of the family.

Does Sibling Rivalry Ever End?

Sibling rivalry in some families does not end, it just takes on different forms and changes in frequency and intensity. As children get older and begin to develop a stronger identity and formulate their own lives and families, sibling rivalry tends to become less of a focus on one’s day-to-day.

When Should You Seek Professional Help for Sibling Rivalry?

Though sibling rivalry is an expected and natural part of development, it is important not to discount the severity of its impact if it goes unchecked. Research backs this up: a study in the Journal of Interpersonal Violence linked sibling bullying to lower self-esteem, sense of competence, and life satisfaction in young adults,² and a 2024 University of York study found sibling bullying at ages 11 to 13 predicts greater mental health difficulties in adolescence. The older ICD-10 classification included a diagnosis called sibling rivalry disorder (F93.3), marked by unusually intense jealousy beginning in the months after a younger sibling’s birth.³ The current ICD-11, in effect since January 2022, no longer treats sibling rivalry as a distinct mental disorder; in US clinical coding it is recorded as a family-relationship problem (Z62.891) rather than a diagnosis. That shift does not make severe rivalry less serious, it simply reflects that clinicians treat it as a family dynamic to address rather than a disorder in the child. If sibling rivalry does not improve with intervention, you notice changes in your child(ren)’s mental health and well-being, and/or you notice a negative impact on their other peer relationships, it may be beneficial to explore a higher level of care. Fortunately, now more than ever there are more ways to access support, with online therapist directory, online therapy platform and online psychiatrist options, there are many ways to find support for one or more children, or the family as a whole.