Final answer:
Inattentive symptoms of ADHD typically become noticeable when children enter school-age years. Young children's attention spans naturally vary, and symptoms must persist for more than six months and be inappropriate for their developmental level to consider a diagnosis of ADHD.
Step-by-step explanation:
When Do Inattentive Symptoms of ADHD Become Noticeable:
Inattentive symptoms of ADHD generally become noticeable at different ages for different children, but it is less common for these signs to be recognized as potentially problematic before the child enters school-age years. Young children, like the 3-year-old son of the concerned mother in the question, often display varying attention spans, which can fluctuate due to their normal development stage.
Attention spans tend to be very limited until around age 11. ADHD symptoms, which include inattention, executive functioning difficulties, impulsivity, and hyperactivity, can manifest differently in each individual and are not exclusively identifiable based on age. For a diagnosis, a child must display symptoms for more than six months and to a degree that is inappropriate for their developmental level.