"Blood Feud" is the twenty-second and last episode of the second season of "The Simpsons". It was first shown on the Fox network in the United States on July 11, 1991. In this episode, Mr. Burns falls ill and badly needs a blood transfusion. Homer learns Bart has Burns's rare blood type and wants his son to donate some, promising Bart that they will be handsomely rewarded. However, after getting the blood, all Burns does is send the family a card. Homer, who is mad, writes a rude reply, but Marge tells him at the last minute not to send it, although Bart mails it anyway.