What are the symptoms of separation anxiety?

Several things: I assume you mean what happens with a child when his or her parents leave? Many believe this has to do with the reactions upon departure and the child's change in behaviors. In fact, separation anxiety can occur upon re-unification. What happens, especially with younger children is for example, when mommy comes back and the child sees her, the child becomes unglued realizing she was gone.

Normal at 8-14 mo: 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. They are inappropriate for older children and may indicate separation anxiety disorder.