Emotional Regulation and Sibling Adaptation to the Arrival of a Newborn

The arrival of a newborn is an event of extraordinary importance for the family, capable of arousing joy, emotion, and a sense of renewal. At the same time, however, it represents a challenge that deeply affects daily life and the relationships within the family unit. While for parents the birth is often accompanied by feelings of happiness and responsibility, for the firstborn it is a delicate transition that involves the need to share attention, care, and affection with a new member of the family.

This change, though natural, can awaken ambivalent feelings in the child: on one hand, curiosity and a desire to care for the baby brother or sister; on the other, jealousy, sadness, or fear of being “replaced” in the parents’ hearts. It is precisely within this ambivalence that much of sibling adjustment takes place.

Every child reacts differently to the arrival of a sibling. Some show enthusiasm and a desire to help, while others express discomfort through more complex behaviors. The most common reactions include:

• behavioral regressions (returning to bottle-feeding, using a pacifier, simplified speech, difficulties with sleep or toilet training),
• tantrums, protests, temper outbursts, irritability,
• aggressive behaviors directed toward the newborn or the parents,
• withdrawal, sadness, and isolation.

Psychological Impact on the Firstborn

The arrival of a new family member represents a crucial event that can reactivate in the firstborn dynamics related to rivalry, fear of abandonment, and competition for parental love and attention. In the literature, sibling jealousy is described as a complex emotional response that includes feelings of sadness, anger, frustration, and exclusion, stemming from the perception of an unequal distribution of parental care. In the first months after a sibling’s birth, it is normal for the firstborn to show some behavioral changes.

As psychologist Judy Dunn has observed, many children tend to return to earlier behaviors: they may ask for the bottle again, wet the bed despite having achieved bladder control, speak in baby talk, or refuse to do by themselves what they previously managed to do, such as dressing or using the potty.

These behaviors, which may seem like “steps backward,” are in fact a way for the child to attract the parents’ attention and feel once again at the center of their care. They are not a real problem, but a natural strategy through which the firstborn seeks reassurance during an important period of change.

When a baby brother or sister is born, it is normal for the firstborn to display a wide range of reactions. Some fall within what researchers consider a natural adaptation process, but if they become too intense or persistent, they may signal distress.

As psychologist Barbara Volling has noted, there are two main categories of responses:

• “internal,” such as anxiety, sadness, withdrawal, or psychosomatic symptoms (stomachaches, headaches),
• “external,” such as aggression, irritability, disobedience, or provocative behavior.

Another researcher, Laurie Kramer, described the arrival of a sibling as a kind of “test to overcome” for the child, one that challenges their ability to manage emotions and behavior. The reactions depend largely on the child’s temperament, the quality of their bond with their parents, and how well the parents manage to reassure and involve them after the baby’s birth.

It is important for parents not to interpret these behaviors merely as “tantrums,” but as messages through which the child communicates a need to feel loved and important. For example, displays of anger may be a way of regaining a sense of control in a situation that feels new and sometimes unsettling.

Parental Support Strategies

What can parents do? First, observe the signs carefully, welcome the emotions, and reassure the child with simple phrases such as, “It’s normal to feel jealous when a baby brother or sister arrives.” Small daily gestures—such as setting aside special moments for the firstborn or involving them in age-appropriate tasks—help reduce the risk of jealousy becoming a bigger issue.

1. Prenatal Preparation and Anticipatory Narration

Implementing early interventions can significantly help reduce the negative reactions of the firstborn. Brody and colleagues (1992) highlighted the importance of prenatal preparation, noting that providing the child with age-appropriate information during pregnancy fosters a more harmonious adjustment to the newborn’s arrival. A key component of this process is anticipatory narration: through stories, picture books, or role-playing activities, the firstborn can symbolically represent the upcoming change and process it on both cognitive and emotional levels.

2. Active Involvement in Caregiving

An important support strategy involves including the older sibling in caregiving practices. Small tasks—such as handing over a diaper, helping during bath time, or choosing the baby’s clothes—provide valuable relational experiences. On one hand, they strengthen the child’s sense of self-efficacy and belonging within the new family structure; on the other, they promote self-esteem and the perception of having an active, recognized role in the family, thereby reducing feelings of exclusion or jealousy.

However, it is essential that this participation not take the form of an obligation. Tasks and responsibilities must be adapted to the child’s age, cognitive abilities, and emotional readiness. Only in this way can the experience be positive and not a source of stress. When properly managed, this process facilitates the firstborn’s integration into the new family structure, turning a potential crisis into an opportunity for emotional and relational growth.

3. Exclusive Time with Parents

Spending exclusive time with the parents is a fundamental strategy to support the firstborn in adapting to the arrival of a sibling. Studies by Volling and colleagues have shown that moments dedicated solely to the older child, even brief ones within the daily routine, help maintain the continuity of the dyadic bond and reduce the risk of separation anxiety.

From this perspective, the concept of “psychological presence” developed by Winnicott takes on central importance: what matters is not the quantity of time spent together, but the quality of the relationship—the parent’s ability to be genuinely present and attuned to the child’s emotional needs.

When practiced consistently and sensitively, these educational approaches allow the firstborn to feel seen and valued, preventing feelings of exclusion and strengthening family cohesion. Thus, the birth of a sibling becomes not just a redefinition of roles but also an opportunity for relational and emotional growth for the entire family.

4. Emotional Validation

Emotional validation also plays a key role. Giving voice to feelings of jealousy or sadness without judgment allows the child to make sense of their emotional experience and integrate it, preventing it from manifesting solely through dysfunctional behaviors. Simple phrases like, “It’s normal to feel a bit sad when things change,” are effective tools for both emotional regulation and the development of mentalization skills.

Integrating the firstborn into the new family balance is a delicate process that requires caregivers to adopt specific relational strategies. Preventing sibling conflicts and fostering cooperative bonds depend on parental sensitivity, respect for each child’s adaptation pace, and the ability to validate emerging emotions. In this way, jealousy and competition are not denied but transformed into opportunities for emotional and relational learning.
Finally, healthy emotional regulation at the family level not only safeguards the firstborn’s well-being but also promotes the harmonious development of the entire family unit. A potentially difficult phase, such as the arrival of a new family member, can become an opportunity for growth for everyone, strengthening cohesion and fostering shared emotional competence.