who was he to successor of?
Pedro II
Afonso, Prince Imperial of Brazil
Afonso was healthy, and as the eldest son of Pedro II, was heir to the throne and styled "Prince Imperial". 
who was afonso? Prince Imperial and heir apparent to the throne of the Empire of Brazil. when was he born? 23 February 1845
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Afonso, Prince Imperial of Brazil [SEP] Life and impact
A letter written by Pedro II to his elder sister Maria II a few months after the birth of his second child—a daughter named Isabel—displayed his happiness: "No news here save the good state of health of myself, of the empress, and of the little ones, who are becoming increasingly cute, principally little Afonso, who is already walking and who says many words, still half incomprehensible, the which increases their charm."