The Failure of Language
Ironically, the poem suggests repeatedly that language is ill-equipped to deal with grief. Heaney's handling of this theme begins with the title, which is deliberately understated and oddly disconnected from the tragic circumstances being described. The characters who grieve most deeply—that is to say the family of the deceased—find themselves at a loss for words, crying or sighing but never discussing their loss. Even the speaker, when addressing the reader, is vague and oblique, avoiding a direct description of what has occurred. Meanwhile, the family's visitors try and fail to comfort them as they fall back on ineffective cliches. Grief, Heaney suggests, cannot be adequately addressed through linguistic means.
Death
The death of a very young child in this poem is so shocking that it alters and subverts every surrounding family relationship. The laughter of the baby appears not life-affirming or joyful, but haunting and almost offensive. The oldest child, our speaker, becomes a kind of parent to his own parents, holding his mother's hand and greeting guests when his father is incapacitated by tears. Meanwhile, gender norms fall away in the presence of death: the speaker's normally stoic father is uninhibitedly emotional, while his mother is angry and silent. In the greatest subversion of all, a young child's life is cut short while older family members live on. In other words, the unnatural and unexpected death of a child renders all other norms surrounding age, family roles, and life cycle strange and pointless.
The Subjective Quality of Mourning
Heaney’s poem is, among other things, an argument that there is no “right” way to mourn—and in fact that intense mourning can make it difficult to observe norms of politeness and proper behavior. The poem's speaker feels unable to express the emotion expected of him, and he feels embarrassed by communal mourning rituals: only when alone with the body of his brother is he able to confront his loss in any real sense. The mother, meanwhile, reacts with anger instead of tears, and the baby, in the greatest subversion of "proper" mourning behavior, is happily unaware of its family's loss. These family members, Heaney makes clear, are deeply upset, and their inability to conform to expected behaviors is a sign of their sadness.
