Separation anxiety refers to a developmental stage in which a child experiences anxiety due to separation from the primary care giver (usually the mother). This phase is fairly standard at around 8 months of age and can last until the child is 14 months old.
In young children, unwillingness to leave a parent or a caregiver is a sign that attachments have developed between the caregiver and child. The child is beginning to understand that each object (including people) in the environment is different and permanent. Young children do not yet understand time, therefore they do not know when or even if a parent will ever come back. Children at this stage struggle between the desire to strike out on their own and the need to stay safe by a parent or caregiver's side.
While separation anxieties are normal among infants and toddlers, they are inappropriate for older children and may indicate separation anxiety disorder. To be diagnosed as such, the symptoms must cause distress or affect social, academic, or job functioning and must last at least 1 month.
Infants experience various emotions as they develop, usually in a relatively predictable sequence. Before 8 months, they are so new to the world that they cannot easily gauge what is ordinary and what may be dangerous, so new situations or experiences seem usual, not frightening.