The world can be a scary place when you are a kid, and it can be scary for many, many reasons. If a child is scared of a parent’s not returning for him, a parent would first want to try to figure out what thoughts are running through his mind. For example, if there was a time when the parent was late, or the child thought the parent had left him (when she really had not), a child could remember that situation and generalize it to all other situations. Sometimes a child has seen something on television or heard about something that would make him think that parents don’t always return. Or there may be situations that are going on or have happened in a child’s life that lead to a child’s worries: for example, if there has been a death in the family or if the parent is a single parent, a child may worry that if something happens to that parent he will be “all alone”. When it is not apparent what the thought is, a parent can try to ask the child questions to get to what he is thinking (e.g., asking him what would happen if a parent didn’t show up, why would a parent not show up, and so on). Sometimes, though, a parent just needs to make her best guess.
Once a parent figures out the thoughts, she can help the child change those thoughts by adding new ones. So, let’s say that a child thinks that a parent will some day forget to pick him up, and then he would be all alone and couldn’t take care of himself. Then, a parent can teach him the replacement coping thought of “Mom has never forgotten to do come back and get me, and she loves me too much to ever leave and not come back. And if I she ever were late, I know her cell phone number, and whoever is watching me will not leave until she gets there.” A parent would then practice this thought with him over and over until he can repeat it back easily and automatically. Then, before she would leave, she would have him practice again, and then have the adult watching him practice it with him. It is often best to gradually expose a child to what he fears: so, for example, a parent could start with situations that only scare a child a little (for example, perhaps leaving him with another adult whom he loves and trusts a lot) and gradually work up to harder ones. A parent could then praise a child when he handles it well, and keep a chart with one column showing all of the times that mom leaves and returns and one in showing the ones in which she does not, so he visually see the odds of her returning.
Of course, if the fear is so severe that it interferes significantly in a child’s life, a parent should seek professional help for the child.