Here are a few examples of assonance in the poem:
* "O mother, where is my brother?" (line 3)
* "She sits with pen and paper / A list of her dead sons" (lines 14-15)
* "Her eyes are wide and staring" (line 18)
* "He writes a letter to the mayor; / He writes of his heart's despair" (lines 27-28)
The use of assonance in this poem helps to create a sense of urgency and emotion, and it adds to the overall impact of the poem's message.