Final answer:
The nurse would expect to note the presence of Reed-Sternberg cells if a 12-year-old child had Hodgkin's disease.
Step-by-step explanation:
If a 12-year-old child is suspected to have Hodgkin's disease, the nurse would expect to note the presence of Reed-Sternberg cells if this child had Hodgkin's disease. Reed-Sternberg cells are large abnormal cells that are characteristic of Hodgkin's disease. Other diagnostic studies, such as imaging tests and blood tests, are also performed to confirm the diagnosis of Hodgkin's disease, but the presence of Reed-Sternberg cells is a key feature.