José was born on 4 September of 1761 and baptized on 22 October 1761, the son of Salvador and D. Mariana Teresa. His godfather was none other than the King of Portugal, D. José I. The baby was "touched" on behalf of the king by the 4th Marquis of Marialva. This is no doubt due to the role that his parents played during the Távora Affair. The king would also be godfather again to another of their children.
An article regarding his parents notes that "he passed away as soon as he was born" which seems to infer that he died in infancy (source to be added), however, I was unable to find the death record in 1761 in Ajuda.
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