Final answer:
Leukemia, a type of cancer affecting blood cells, can cause thrombocytopenia, or a low platelet count, which makes blood clotting difficult and leads to an increased risk of bleeding.
Step-by-step explanation:
The child with leukemia has a condition known as thrombocytopenia, which is characterized by an insufficient number of platelets leading to an increased risk of spontaneous bleeding. Platelets are vital for blood clotting, as they stick to the injured areas and release clotting factors, which are essential for the formation of a clot to stop the bleeding. In leukemia, abnormal blood cells begin to crowd out normal blood cells in the bone marrow, which can include the cells responsible for the production of platelets, thereby contributing to thrombocytopenia. This can result in challenges with blood clot formation and consequently lead to excessive bleeding, even from minor injuries. It's important to note that abnormal function or insufficient platelet production can be a serious condition, and adequate medical attention is crucial.