Hi, it is normal for babies and toddlers to feel anxiety when separated from parents. Because parents are basic caregivers at this age children often feel like something bad is going to happen if they are separated. However, a child can be distracted and calmed down. Separation anxiety becomes a disorder if a child feels this anxiety after the age of five, or when the anxiety interferes with normal activities and lasts for days. The problem in your daughter might have aroused because you didn't prepare her for the separation. This disorder is a manifestation of child's fear that something might happen to parents or her if they are separated. These children often fear that if they are left alone the parents might never return. This is why they follow their parents around the house and don't like to be left alone. The child affected with separation anxiety disorder is often scared to go to asleep by herself and appears in the parents' bedroom in the middle of the night. These are just few patterns of the behavior that child with separation anxiety disorder might display. You might have noticed them, but didn't think much of it because you were not familiar with this disorder. You should not worry too much because separation anxiety disorder can be treated successfully with the help of cognitive behavioral therapy that focuses on helping the child learn skills to manage anxiety and control situations that contribute to anxiety.