A particular level of separation anxiety is an expected and is a healthy part of normal development that occurs in all children to varying degrees between infancy and age 6. Healthy separation anxiety is typically first seen around 7-11 months of age, when an infant becomes anxious when meeting strangers (this is called stranger anxiety ). Children also may become mildly anxious around 18-24 months of age, when they are increasingly exploring their world but wanting to return to their caregiver frequently for security.

Contrary, children with separation anxiety disorder have separation worries that are excessive and much greater than their peers. These worries can overwhelm a child, even when they involve brief separations, such as leaving to go to school, going to sleep, or staying behind at home when a parent runs an errand. The child's fears may appear to be irrational, such as the fear that the parent may suddenly die or become ill.

Young people with separation anxiety disorder often go to great extremes to avoid being apart from their home or caregivers. They may protest against leaving a parent's side, refuse to play with friends, or complain about physical illness at the time of separating. Frequently, a child tolerates separation from one parent more easily than separation from the other parent.

Diagnosing separation anxiety disorder can be challenging because children with separation anxiety disorder may have more than one anxiety disorder. Children with separation anxiety disorder frequently have physical complaints, which also may need to be medically evaluated. A trained clinician (such as a child psychiatrist, child psychologist or pediatric neurologist) should integrate information from home, school, and the clinical visit to make a diagnosis.

At home, children with separation anxiety disorder may experience a combination of the symptoms listed below.

a) Frequent physical complaints at times of separating . Children with separation anxiety disorder often complain about stomach aches, headaches, or other physical discomforts when they know they will have to separate.
b) Terrifying dreams about being separated
c) Consistent and extreme worry and fear when separating from home or primary caregiver. Children also may be extremely frightened and worried when they anticipate separation and may be unwilling to be alone.
d) Difficulty sleeping alone . Children may insist that a parent sleep with them or may insist on sleeping with the parent in the parent's bed.
e) Recurrent worry and fear that something bad may happen to their parent or to themselves. They may worry about a parent becoming sick or getting hurt. They also may worry about getting lost if separated.
f) Refusal to attend school often develops, due to worries about separating
g) Refusal or reluctance to participate in ordinary outings or activities . The child may not want to go out to dinner, meet friends to play, or engage in after- school programs.

If left untreated, the condition may lead to considerable limitations in other areas of the child's life. Peer relationships, school functioning, and family functioning may suffer, or depression may develop. In some situations, if a child believes there is no way to reduce extreme anxiety, thoughts of self-harm or not wanting to be alive may develop. Professional help should be sought in such cases.