While the affair is taking place, the parent involved in the affair is often focusing at least part of his emotional time and energy outside the home. Often the parent is not even aware that his focus is elsewhere. Children sense that they have become less important or that the parent is spending less time with them and this can cause them to feel anxious, frightened and rejected. These feelings can be exhibited as symptoms including bed-wetting, clinging, thumb-sucking and other attention-seeking behaviors.

Older children who find out their parents are having extra-marital affairs often take the affair as a personal affront. These children may act out, whether it is in the home or at school. Children feel that when the cheating parent tells lies, the parent is not only lying to the spouse but to the child as well. Similarly, if the parent uses the excuse of not being happy in the relationship for her affair, the child feels that they are part of the parent's unhappiness. Acting out becomes the child's way of trying showing anger towards their parent.

Girls whose fathers have cheated on their mothers face particular issues. They often grow up angry at men and unsure of their relationships because they have learned from experiences that men can cheat. They also lose confidence and have lower self-esteem because they have had to watch their mothers dishonored by their fathers.

Children whose parents have had extra-marital affairs may grow up to have affairs of their own. This association is particularly strong in boys whose fathers were not remorseful of their own affairs. Boys in these situations come to see affairs as normal activities or appropriate solutions to marital problems. Children also grow up perceiving sex as a casual act and fidelity as something that can be broken.