The medical team who treated your husband should give you the final explanation. What I can share to you, Mrs. Temple, is that chemo makes the white blood cell drop significantly, white blood cell is the guard in the immune system, white blood cell drop means higher chance of infection, and sepsis is a type of serious infection. However it doesn't happen in every chemo case as you know, I can't say everything has been done right during the whole thing. You will need to get the information from the hospital and medical team.