A Separate Peace, written by John Knowles is a flashback to the main character, Gene Forrester's studies at the Devon School in New England. During this flashback Gene remembers his best friend Finny, who was really athletic and outgoing. Gene and Finny's friendship was one of jealousy. Gene was jealous of Finny's talent in athletics, and Finny was envious of Gene's talent in school. Eventually, Gene's jealousy towards Finny takes over and causes him to shake the tree branch which causes Finny to fall and break his leg. The fracture was bad, but it wasn't until Finny fell down the stairs and broke his leg again that he had to have surgery. The surgery Finny would undergo would cause further complications and heartbreaking news for Gene. During the surgery Finny would lose his life due to some bone marrow leaking into his bloodstream and preventing his heart from beating. “As I was moving the bone, some of the marrow must have escaped into his bloodstream and gone straight to the heart and stopped it” (Knowles 193). Although people don't normally think of bone marrow as an important part of the human body, it can cause big problems if it needs to be replaced or if it leaks into the bloodstream. First of all, bone marrow is very often one of the forgotten body parts, but it is necessary for the bones of the hips and thighs to function properly. Bone marrow is the soft, fatty tissue found inside bones. Inside the bone marrow there are cells called stem cells. These stem cells turn into red and white blood cells and also platelets which help blood clot. Even though stem cells are supposed to turn into blood cells, there can sometimes be problems with how the stem cells fall into the middle of the paper, destroying all the healthy bone marrow in the body. . As a result, the patient will have to undergo a process to replace all the deteriorated or damaged bone marrow. This process involves taking stem cells from a donor and transplanting them into the patient's body, so that the patient turns these stem cells into bone marrow. Bone marrow can also pose a complication to the body if it leaks into the bloodstream. If bone marrow enters the bloodstream, it can travel throughout the body and cause serious complications. This is a condition called fat embolism and occurs mainly after severe trauma or surgery to the lower extremities. There is no specific diagnosis or treatment for this; is based primarily on the patient's condition or symptoms. Bone marrow can be a very dangerous thing if it has any kind of complication inside the body.