By Rabia GÜRER GÜRKAN, Senior Child Development Specialist

Human beings are inherently social. From the moment a baby is born, they seek connection—with caregivers, voices, touch, eye contact, and later, shared emotions and social rules. Social development in the first two years of life refers to how babies begin to understand themselves in relation to others, develop trust, learn empathy, and lay the groundwork for friendships, cooperation, and emotional regulation.

This article explores the science behind social development in infants and toddlers aged 0–24 months. With insights from child psychology, pediatrics, neuroscience, and global early childhood research, it offers a practical and evidence-based guide for families and professionals worldwide. 

Section 1: What Is Social Development?

Social development in the first two years involves:

Recognizing and bonding with caregivers

Expressing and responding to emotions

Understanding social cues (e.g., smiling, tone of voice)

Developing a sense of self and others

Beginning social play and cooperation

These early social behaviors are closely tied to emotional development, and together they form the basis for future relationships, identity, and mental health.

Section 2: Developmental Milestones by Age

Based on CDC, WHO, and Harvard Center on the Developing Child guidelines:

0–3 Months

Responds to voice and touch

Smiles in response to social interaction

Begins to mimic facial expressions

4–6 Months

Laughs out loud

Enjoys peek-a-boo and similar games

Turns to familiar voices

7–9 Months

Shows attachment to caregivers

Develops stranger anxiety

Tries to attract attention with gestures or sounds

10–12 Months

Engages in joint attention (looking where adult points)

Waves “bye-bye,” claps

Seeks comfort when upset

13–18 Months

Imitates adult behaviors

Shows empathy (e.g., concerned when others cry)

Plays alongside others (parallel play)

19–24 Months

Shows preference for familiar people

Engages in pretend social play (feeding a doll)

Begins cooperative play with peers

Section 3: The Science of Attachment

Attachment theory, developed by John Bowlby and expanded by Mary Ainsworth, emphasizes that a secure emotional bond with a primary caregiver is the cornerstone of healthy social development.

Securely attached babies feel safe exploring the world because they trust their caregiver will return.

Insecure attachment (from neglect, inconsistency, or trauma) can lead to anxiety, fearfulness, or withdrawal.

Research shows secure attachment leads to:

Better emotion regulation

Stronger peer relationships

Higher self-confidence (National Scientific Council on the Developing Child, 2022)

Section 4: Role of Caregivers in Social Development

Responsive caregiving is crucial. Parents and caregivers can support social development by:

Making eye contact during feedings and diaper changes

Talking through emotions (“You look sad—do you want a hug?”)

Modeling positive interactions with others

Offering consistent routines to build trust and predictability

In global research, “serve-and-return” interactions—where babies gesture or vocalize and adults respond—are shown to stimulate brain regions linked to social understanding.

Section 5: Emotions in the First Two Years

Babies begin life with basic emotional reactions (comfort/discomfort), but their emotional range expands rapidly:

By 6 months: Joy, surprise, anger, fear

By 12 months: Embarrassment, jealousy

By 24 months: Guilt, shame, pride

Social development includes learning how to express and respond to emotions appropriately, a process called emotional regulation.

Section 6: Cultural and Environmental Influences

Social behavior is shaped by culture. Examples:

In Japan, babies are encouraged to be quiet and socially aware.

In the U.S., independence and assertiveness are emphasized.

African and Latin American cultures may stress extended-family bonds and group play.

However, secure, responsive care is universally beneficial.

Section 7: Red Flags in Social Development

Watch for signs that may indicate delays or social-emotional concerns:

No social smile by 3 months

Lack of eye contact by 6 months

No response to name by 12 months

Doesn’t show interest in others by 18 months

Doesn’t engage in pretend play by 24 months

If concerns arise, early intervention (such as speech therapy, child psychology, or parenting programs) is highly effective.

Section 8: Social Play and Its Evolution

Play is how babies learn social rules.

Types of play in early years:

Solitary play (0–12 months): Babies play alone but observe others

Parallel play (12–24 months): Play alongside others without interaction

Associative and cooperative play (emerges after 24 months)

Caregivers can support play by:

Providing diverse toys (puppets, dolls, mirrors)

Organizing safe playdates

Playing interactive games like peek-a-boo and pat-a-cake

Section 9: Social Impact of Siblings and Peers

Siblings and peers introduce babies to:

Sharing and turn-taking

Dealing with conflict

Learning social norms and language

Even negative interactions (e.g., toy grabbing) can teach important social skills—if guided appropriately.

Section 10: Screens, Social Isolation, and Pandemic Effects

Recent years have raised new questions:

Too much screen time in infancy can reduce face-to-face social learning (AAP, 2023).

Babies born during the COVID-19 pandemic showed delayed social milestones due to isolation (Nature, 2021).

Recommendations:

Limit screens under 18 months

Prioritize real-life interaction

Use video calls meaningfully with distant family members

Section 11: Activities to Support Social Development

0–6 Months

Skin-to-skin contact

Mimic faces and sounds

Smile and speak often

7–12 Months

Mirror games

Pointing and naming objects

“Where’s mommy?” games

13–18 Months

Pretend feeding stuffed animals

Peek-a-boo with peers

Dancing to music together

19–24 Months

Role play (doctor, parent)

Storytelling with expression

Cooperative building (e.g., towers)

Conclusion

Social development in the first two years sets the stage for a child’s emotional health, relationships, empathy, and sense of self. From warm eye contact to guided play, every moment of responsive care helps babies grow into emotionally intelligent, connected human beings. For parents and caregivers, these years are an opportunity not just to raise a child—but to shape the future of human empathy.

For parents and caregivers, these years are an opportunity not just to raise a child—but to shape the future of human empathy.”

Neuroscience confirms that early social experiences shape brain architecture for life.

Scientific References

American Academy of Pediatrics (AAP). (2023). Screen Time and Social-Emotional Development.

Bowlby, J. (1969). Attachment and Loss.

CDC (2023). Social and Emotional Milestones.

Harvard University – Center on the Developing Child. (2022). Serve and Return Interactions.

National Scientific Council on the Developing Child. (2022). The Science of Early Childhood Development.

Nature. (2021). Pandemic and Infant Social Development.

WHO. (2022). Nurturing Care for Early Childhood Development.