Stranger anxiety is a form of distress that children experience when exposed to people unfamiliar to them. Symptoms may include: getting quiet and staring at the stranger, verbally protesting by cries or other vocalizations, and hiding behind a parent.

Stranger Anxiety
Stranger Anxiety
Stranger Anxiety
The familiar stranger:anxiety, comfort, and play in public places
Infant and Stranger Variables Related to Stranger Anxiety in the First Year of Life.
Early Predictors of Separation Anxiety Disorder: Early Stranger Anxiety, Parental Pathology and Prenatal Factors
Elective mutism: Origins in stranger anxiety and selective attention.
“Hitomishiri” as a Japanese Concept of Stranger Anxiety and Anthropophobia
Separation and Stranger Anxiety
Stranger Anxiety: Failed Legal Equivalences and the Challenges of Intimate Recognition in Taiwan
Behavioral Markers of Emergent Stranger Anxiety in Infants and Toddlers with Fragile X Syndrome
Verbal Transmission of Stranger Anxiety from Parents to Children
Stranger Anxiety: When Children Face Strangers