The poem "My brother, you must not die," was written by Yosano Akiko. She is the one speaking in the poem. She is speaking to her younger brother, as she begs of him not to get involved in the Russo - Japanese War. She does it by letting him know of all the things he has to live for, and he wasn't taught and made to kill people.
In the lines 4 - 9, she describes the ways her parents have raised her brother. The parents did not raise him for twenty-four years to hold a sword and kill a person, and they certainly did not want him to take a chance ending his life. She wants him to carry on the family name of a merchant in Sakai, and to take care of his mother and wife. Their mother is now widowed, and needs her son so the house isn't all alone.
In line 29, it says she's pathetic in her grief. So she must be dissapointed in her son for wanting to go. I think the mother is really worried because in line 32, it tells how her white hair increases. That's either a sign of aging or worrying too much about her son dying.
The brother has been married for ten months. Akiko reminds her brother of the misery and pain he will put his wife and mother through if he dies, and how it will be hard for them to continue life without him.
I think the reason the brother wants to go and fight in the war is because he wants to be remembered as a great fighter of a war. Like in line 22, it says, "In death is your glory," the brother knows the consequences of going off to war. I...