I remember your post. In fact, I remembered it distinctively just 2 days ago when my neighbor came over and shared her story of her newly engaged daughter. This daughter’s fiancé just had his 2nd dose of the Pfizer vaccine (Late June) and within days started experiencing difficulty breathing, which led to a few ER visits and multiple doctor visits. Lots of other treatments which I don’t remember. Final diagnosis is leukemia. He is late 20s. I’m so sorry to hear about your brother. My heart goes out to you.