What is ironic about Okonkwo's feelings for Ikemefuna, in contrast to his feelings for Nwoye in Things Fall Apart?

It is ironic that Okonkwo loves Ikmefuna like a son. He is
the young man that he wishes Nwoye would have been. Although Nwoye is Okonkwo's
biological son, Okonkwo favors Ikemefuna. Ironically, Ikemefuna is Okonkwo's choice for
a son:

From
the beginning, Ikemefuna fills the void in Okonkwo's life that Okonkwo's own son
cannot.

Okonkwo is pleased
with the young man that Ikemefuna is. He wishes that Nwoye had the tendencies that
Ikemefuna has. Everyone falls in love with Ikemefuna:

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He earns everyone's love and respect because he
is so lively and
talented.

Ikemefuna is gifted
at the masculine traits. This pleases Okonkwo. Ironically, Okonkwo chooses Ikemefuna
over Nwoye. Ikemefuna has become Okonkwo's son. Okonkwo truly appreciates Ikemefuna for
teaching Nwoye to be a man:

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Ikemefuna already knows much about the world and
can do almost anything. He can identify birds, trap rodents, and make flutes. He knows
which trees make the best bows and tells delightful folk stories. Okonkwo appreciates
Ikemefuna for the example he sets for
Nwoye.

It is ironic that
Okonkwo would favor Ikemefuna over his own biological son. One would think that Okonkwo
would not show the favoritism that he does. Clearly, Ikemefuna is Okonkwo's choice.
Ikemefuna pleases Okonkwo. Ironically, Nwoye does not have his father's
heart.