Career
She was the only child of Pedro I born out of wedlock who was officially legitimized by him. On 24 May 1826, Isabel Maria was given the title of "Duchess of Goiás", the style of Highness and the right to use the honorific "Dona" (Lady). She was the first person to hold the rank of duke in the Empire of Brazil.
These honors did not confer on her the status of Brazilian princess or place her in the line of succession.
In his will, Pedro I gave her a share of his estate. She later lost her Brazilian title and honors upon her 17 April 1843 marriage to a foreigner, Ernst Fischler von Treuberg, Count of Treuberg.
He accorded her equivalent official honors, such as having her greeted by the Imperial guard and in naming her protector of the province of Goias. From 1829, she was educated at the Ecole du Sacré-Coeur in Paris.
When the family left for Portugal, however, she remained.