Is Sibling Rivalry Normal? How Conflict Between Siblings Works

Medically reviewed by Elizabeth Erban, LMFT, IMH-E
Updated April 19, 2024by BetterHelp Editorial Team

Conflict between siblings is common among Western families. However, the degree of conflict and frequency of negative interactions varies considerably from family to family. For some, occasional small bouts of bickering might be the norm, while other families might have frequent interactions between siblings that resemble bullying or other harmful behavior.

While a small amount of conflict between siblings might help them improve and grow, evidence indicates that frequent or severe conflict can seriously impact mental health and self-esteem. This article will explore the nature of sibling rivalry and offer suggestions for improving sibling relationships.

Does sibling conflict impact your life?

Theories of sibling relationships and sibling conflict

The social and family sciences have spent considerable time studying sibling dynamics among modern families. Despite that effort, researchers are still developing a comprehensive theory explaining how siblings' relationships evolve through childhood, adolescence, and adulthood. A few modern theories are described below:

Social learning theory

One of the best-evidenced and most widely discussed theories to describe sibling dynamics relies on the fact that children are constantly learning by observing the behavior of those around them. Children's behavior can also be changed by instructing them directly, such as when a parent reprimands a child for poor behavior. When a child watches a natural interaction, such as two parents communicating healthily, they learn indirectly. When a parent or other authority figure instructs or redirects a child, they learn directly.

Most of what a child learns regarding how they should act in various situations comes from indirect learning. This concept is reflected in modern approaches to family therapy, which strongly emphasize the importance of parents modeling good behavior for their children. The importance of indirect learning also applies to sibling relationships. Similarly aged siblings likely learn how to interact appropriately with others by observing their parents. When there is an age difference between siblings, younger siblings may look to older siblings as examples of behavior.

Parents who model good communication and conflict resolution give their children the tools to engage in healthy relationships with others, including their siblings. Conversely, parents who model high-conflict behaviors teach their children that unhealthy communication and poor conflict resolution are the norm. While the effect of indirect learning and modeled behavior is substantial, direct learning also plays a role. 

Attachment-based theories

The study of attachment theory was first concerned with parent-child relationships, especially maternal relationships. Since its development in the mid-20th century, attachment theory has become one of the most widely accepted theories explaining how individuals bond. The theory proposes that a person's relationship with their parents strongly influences how they relate to others. From the very first days of life, the human brain begins to form an impression of what a healthy relationship is and is not.

Children with warm, affectionate, and nurturing parents develop a secure attachment style; they know from a very young age that their parents represent safety and protection. When attachment is assured, children are more likely to explore, interact with others, and openly investigate their surroundings. In contrast, children with parents who are distant or hostile are likely to develop an insecure attachment style. Insecurely attached children may struggle to interact with others, take risks, or venture outside their comfort zone.

Attachment styles impact a person's well-being well into adulthood; evidence suggests that an insecure attachment style can lead to dysfunctional interpersonal relationships, low self-esteem, and mental health concerns. Insecure attachment in childhood may be a source of significant conflict among siblings. Children in the same home may be anxious, more prone to anger, and feel less safe in themselves. In addition, young siblings often form attachments with their older siblings, and if those attachments are insecure, the risk of high-conflict behavior is increased.

Family systems theory

Family systems theory directs attention to the larger context in which sibling relationships develop. The theory organizes families into a hierarchy of influential subsystems. Subsystems might include a parent's marital relationship, relationships between two siblings, relationships between parents and siblings, and so on. Family systems theory also recognizes extended family members, who interact with the family as unique substems that impact the dynamic of the central family unit. 

Each subsystem in the family can impact and be impacted by other subsystems. The subsystems are also hierarchical, meaning they have an order of importance. Some subsystems are more important to maintaining family stability than others. For example, the marital relationship of two parents is likely more important for long-term family stability than the relationship between two siblings.

Family systems theory suggests that sibling relationships are significantly affected by the communication and behavior of other family subsystems. For example, parental conflict can induce sibling conflict by introducing instability into the greater family dynamic. Even if one subsystem doesn't directly introduce conflict, there can still be a significant impact. Consider a family where both parents must work full-time to provide for their children financially. In that case, some parental responsibilities may be pushed onto the eldest sibling, likely impacting their relationship with their younger siblings.

Sibling rivalry among adults

While sibling rivalries are often born out of conflict in childhood, discohesion can also emerge in adulthood. While most siblings report reduced conflict as they move from adolescence into adulthood. However, increased stress or a major shift in family dynamics can initiate new conflicts or cause old conflicts to re-emerge.

Regardless of when conflict appears, the roots of sibling discontent are usually found in childhood. Consider a scenario in which two adult siblings must face the sudden loss of a parent. The siblings, who previously reported little to no conflict, find themselves increasingly at odds regarding how to handle their deceased parent's arrangements and care for their parent, who is still alive. Without knowing the specifics of the siblings' upbringing or adult relationship, it is impossible to know precisely what is causing their conflict, but the theories of sibling relationships described above may offer some insight:

  • Social learning theory might suggest that the siblings' parents did not model coping skills that the siblings can use to process the emotional strain of their parent's death.
  • Attachment theory might indicate that the siblings' are experiencing distress after losing a source of safety and protection. Strong, secure attachment that is established in childhood often carries into adulthood.
  • Family systems theory might propose that the disruption of a highly-influential subsystem – the parent-to-parent subsystem – produces extreme stress among the siblings. The increased stress may introduce conflict that wasn't present when the family unit was stable.

Which theory is correct? In practice, it may be all of them or none. The dynamics of sibling and family relationships are complex, and it is challenging to discern exactly how conflict arises. However, the evidence-based theories described above offer clues and insights into the likely source of conflict. 

Does sibling conflict impact your life?

Building strong sibling relationships

Because most sibling rivalries begin in childhood, it is usually up to the siblings' parents to prevent conflict from developing. This requires modeling good communication skills, demonstrating healthy conflict resolution, and treating children with kindness and empathy. It is important to model the behaviors as consistently as possible, although only some parents are likely to model perfect behavior constantly. Imperfection is acceptable so long as parents use instances of inappropriate behavior to teach children how to correct conflict and problem-solve.

Besides striving to model appropriate behavior, there is one other key piece of advice that experts recommend to reduce the likelihood of sibling conflict: avoid differential treatment. Differential treatment occurs when one sibling perceives that they are being treated significantly differently than other siblings. Differential treatment often appears as favoritism and is one of the strongest drivers of sibling conflict in modern families.

Parents may also consider redirecting sibling conflict when it occurs. When parents intervene in sibling conflict, they allow the siblings to practice conflict resolution and appropriate community. Parents also teach their children which behaviors are appropriate and which are harmful to their relationship with their siblings.

Can online therapy help?

Online therapy is a convenient option to start therapy without leaving your home. If you have children, especially if those children often come into conflict with each other, removing barriers to therapy may be beneficial. You won't need to travel to an office, and you can choose from therapists outside of your nearby area.

An online therapist can help reduce family conflict, manage stress, and increase cohesion. They use the same evidence-based techniques as traditional therapists, like family therapy. A therapist can also help manage conflict between adult siblings or help you manage the stress associated with adult-sibling conflict. Research indicates that modern therapy options like telehealth and online family therapy are effective and more convenient for many families than in-person family therapy


Sibling rivalries emerge due to several factors. Poor parenting, high-conflict households, major disruptions to the family unit, and excessive stress can all produce sibling conflict. While sibling conflict is often rooted in childhood interactions between siblings, sibling rivalries can emerge in adulthood. Although no comprehensive theory accurately describes how all sibling conflict develops, researchers believe that parents who model good communication, treat siblings equally, and proactively handle sibling conflict when it emerges are likely to have the lowest risk of rivalries between their children.

Seeking to explore family concerns in a supportive environment?
The information on this page is not intended to be a substitution for diagnosis, treatment, or informed professional advice. You should not take any action or avoid taking any action without consulting with a qualified mental health professional. For more information, please read our terms of use.
Get the support you need from one of our therapistsGet started