My 27 year old son was diagnosed with Ewings Sarcoma 3 years ago. He had 13 rounds of chemo, 28 sessions of radiotherapy and limb salvage surgery. His last chemotherapy was July 2022. His scans have been clear since then. Before his treatment he was never sick, now he is getting a cold every 4 or 5 weeks. He commutes to work on the train and works in an office. How can he improve his immune system and when should I worry that this is more than just a side effect of his treatment. As a parent every time he is sick my brain goes into overdrive. Thanks