In Chapter 7 of Things Fall Apart, the boy Ikemefuna has lived with Okonkwo, who is pleased with this boy's influence upon his son.
He wanted Nwoye to grow into a tough young man capable of ruling his father's household when he was dead and gone to join the ancestors.
And, the presence of Ikemefuna has made Okonkwo's son become less interested in the stories of the women and more interested in tales of head-hunting and warfare now. With another boy, Nwoye also engages in more manly activities. Ikemefuna has become such a part of the family that he even calls Okonkwo "father."
Unfortunately, however, after locusts come and the tribe gathers them for food, Ogbuefi Ezeudu, an elder in the quarter of Umuofia arrives at the home of Okonkwo. He informs Okonkwo that the Umuofia Oracle has determined that Ikemefuna must be killed in punishment of the crime committed in the past against Umuofia. Ezeudu tells Okonkwo to heed the command, but not to participate in the actual execution because the boy calls him "father." Okonkwo agrees to comply; he calls Ikemefuna the next day and tells him that he is going home. But, when the Umuofia arrive, the boy is skeptical; nevertheless he goes with them.
At the beginning of their journey the men of Umuofia talked and laughed about the locusts, about their women, and about some effeminate men who had refused to come with them.
Oknkwo does come with them, but he stays back, knowing what will happen, yet afraid to disobey. Finally, a man in the rear clears his throat to get Ikemefuna's attention; Okonkwo just looks away.
He heard the blow. The pot fell and broke in the sand. He heard Ikemefuna cry, "My father, they have killed me!" as he ran towards him. Dazed with fear, Okonkwo drew his machete and cut him down. He was afraid of being thought weak.
This act of Okonkwo greatly damages his relationship with his own son, Nwoye, who loves his "brother." When he sees his father return, the son realizes what has happened and "something seemed to give way inside him, like the snapping of a tightened bow."