My four-year-old son has been developing one or two small to medium-sized bruise-like marks on his knees or the lower part of his legs, over the bony areas, about once or twice a week for the past two months. He is very active, playful, and mischievous. He spends most of the day indoors, jumping around and climbing onto tables, so I thought the bruises might be due to that. However, I still consulted a doctor, who advised us to get the following tests done: CBC, CRP, Ferritin, APTT, and Prothrombin Time. His test results are: Ferritin: 23.5 CRP: 0.03 Vitamin d <8 He drinks very little water—less than 250 mL per day. His weight is 13.8 kg. He did not have any active infection at the time of the tests. However, one week earlier, he had received the Influenza and MMR vaccines. His ESR is high. Is there anything concerning about his blood test report regarding bruise? At present, the doctor has prescribed Tonoferon and vitamin d for 3 and 2 months respectively. My son has less fat .