"The Stolen Child" by Yeats is a narrative poem, infused with the sense of the otherworldly, that moves in a progression of introducing the setting, creating the action, furthering the action, and then concluding with the achievement of the goal of the action.
The setting is introduced; it is one of "wandering water gushes" and "hills above Glen-Car." The spirits who call to the child first seek trout, and then they call to the child to come away with them.
The spirits travel far and and dance under the moonlight (Yeats felt that the moon effected cycles of life), going farther and still beckoning to the child, but he is "anxious in his sleep" and not ready to venture into an unknown realm.
The spirits move farther, "whispering to the trout," giving them "unquiet dreams"; here a certain pastoral beauty is created, and the spirits continue to beckon to the child to come away with them.
Away with us he's going,
He'll hear no more the lowing
Of the calves on the warm hillside
Or the kettle on the hob
Sing peace into his breast
The faeries have finally captured the child's imagination and mystified him enough that he comes away with them, away from a world "more full of weeping than he can understand." While these spirits have taken the child, they have also spared him the terrible pangs of life and sung "peace" in his heart.
Yeats's poem is a romantic one in which the sweetness of childhood is preserved only by removing the child from the real world into a mythical one.