Final answer:
Being in remission means the chronic illness like leukemia is present but not active, suggesting successful treatment though not necessarily a cure.
Step-by-step explanation:
To be in remission when one has a chronic illness like leukemia means that the disease is present, but the symptoms are not currently experienced. Remission can occur when a cancer, like leukemia, is treated early and effectively with various modalities such as surgery, chemotherapy, or radiation therapy, which aim to kill cancer cells and reduce the tumor burden. In the case of a four-year-old child with leukemia, remission suggests that while the cancer has not necessarily been cured, the child is not currently showing symptoms of the disease, implying successful initial management of the condition. It is important to note that chronic conditions may flare up again, and ongoing treatment and monitoring are often necessary.