I'm sorry to hear about this. Were you able to discuss the immediate cause of death with her doctors? Vomiting blood may be attributed to bleeding somewhere in the upper GI tract such as the stomach, mouth, throat, esophagus, and the first part of the small intestine. Blood that is vomited may come from any one of these places. With hepatitis B, possible complications include liver cancer, liver failure, cirrhosis, as well as esophageal varices that can bleed. This could be a factor in the vomiting of blood. It is best that you discuss this with the patient's attending physicians also for proper evaluation. Take care and regards.