Answer:
Stranger wariness
Explanation:
Once one baby has developed a secure attachment with his/her caregiver. The phenomenon of stranger wariness starts to appear.
Stranger wariness refers to the anxiety that babies experience when they are approached by an unfamiliar person, specially when they are under novel situations. Since babies prefer familiar adults, they might react with concern, fussing or crying when approached by an stranger.
In this example, Tyra's niece gets a smile from the mail carrier and she hides her face in Tyra's shoulder and looks back at him with concern.
The carrier is an unfamiliar adult who approached to Tyra's niece (by smiling) under a situation that doesn't take place very often (the mail carrier stepping inside the house) so the baby reacts with concern. This is an example of Stranger wariness.
