Retinoblastoma is caused by a retinoblastoma gene mutation. Osteosarcoma may occur as a result of this mutation; it presents with bone pain. This is the most relevant health screening information for the parents because of the patient’s history. Frequent illness and abdominal distention (due to hepatomegaly) reflects acute lymphoblastic leukemia; it is associated with radiation, but the child did not require radiation, so this is a less relevant instruction. Colon cancer, as evidenced by bloody stools, is not a common cancer of children and not related to the Rb gene mutation. Increased intracranial pressure (sclera visible superior to the iris and projectile vomiting) may indicate tumor growth, but there were clean margins, so this is less expected.