Final answer:
The term 'erratic' describes the unpredictable behavior mentioned in the question, which can be linked to certain emotional states or attachment styles in children.
Step-by-step explanation:
The child's unpredictable behavior bothered his parents because he was so erratic. This term describes someone acting in a way that is not predictable or consistent, which can be concerning and perplexing to others. In the context of understanding child behavior and development, it's useful to recognize that children can exhibit a range of behaviors based on their emotional state and attachment styles. For example, children with disorganized attachment may exhibit erratic behaviors, such as freezing or running around aimlessly when a caregiver returns, which is often seen in children who have experienced abuse. Recognizing these patterns can provide insight into a child's emotional needs and help guide proper support and intervention.