Cato is Portia's brother, Brutus's brother-in-law, and a friend to Brutus and Cassius. He dies in the second battle at Philippi.
Cato is described as "Young Cato" in the play's notations. He is a very minor character, appearing only in Act V, Scene 3, when he, along with Brutus and Messala, comes to view the bodies of Cassius and Titinius, and in Act V, Scene 4, when he dies.
Cato is the son of the great Marcus Cato, the brother of Portia and the the brother-in-law of Brutus. In the play he is also a solider in the army of Brutus and Cassius. He has a very short role in the play as he dies fighting for what he believes is honorable at the battle of Philippi. He says these words, which shows his heroic temper:
"What bastard doth not? Who will go with me? I will proclaim my name about the field: I am the son of Marcus Cato, ho! A foe to tyrants, and my country's friend; I am the son of Marcus Cato, ho!"
When he dies, Lucilius says:
"O young and noble Cato, art thou down? Why, now thou diest as bravely as Titinius; And mayst be honour'd, being Cato's son."
Like Brutus, Cato is portrayed as honorable, heroic, and tragic. He fights to the end believing that he is doing what is best for Rome. Even if he is wrong, he cannot help but be honored.
Young Cato is Brutus' brother-in-law, the son of Marcus Cato, and an officer in Brutus' and Cassius' army. In 5.4, he is depicted as intrepid, follows Brutus into battle, and is slain during a fight with Antony's men. Lucilius witnesses his death, proclaims him noble, and says that since Young Cato died as bravely as Titinius, he should be honored.