What events foreshadow Tybalt's death?

First, Romeo gets banished so he has to leave Verona. Second, Mrs. Capulet is so furious with him that she is prepared to send hired murderers to Mantua to kill him. Up to this point Romeo and Juliet hoped, once their marriage was consummated and could not be annulled, that their parents would accept it as a fait accompli. Now, Mrs. Capulet would sooner kill Romeo than accept him as a relative.