Answer:
Nightmares, Night terrors
Explanation:
Nightmares are dreams that cause feeling of unpleasantness, that cause fear, despair, anxiety and sadness. They occur during rapid eye movement sleep.
Night terrors are a sleep disorder that causes panic or dread in person in the first 3-4 hours of non rapid eye movement sleep. They are predominantly found to occur in children and decrease as they grow older.