Final answer:
The nurse should expect to note tachycardia in a 12-month-old child with iron deficiency anemia, as it is a common finding due to inadequate oxygen transportation.
Step-by-step explanation:
The nurse should expect to note tachycardia in a 12-month-old child with iron deficiency anemia. Tachycardia refers to a rapid heart rate, which is a common finding in individuals with anemia. Iron deficiency anemia occurs when there is a decrease in the number of red blood cells due to insufficient iron levels. This can lead to inadequate oxygen transportation, causing the heart to work harder, resulting in an increased heart rate.