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Queen Maria I MARRIED her paternal uncle, who became co-sovereign as King Pedro III. So I'm not sure if that example really counts: it might otherwise have been difficult for her to inherit the Portuguese throne in her own right.

Portugal never abided to the Salic Law.
King D.José only had daughter, so, despite he had one living brother, the succession would always fall on his eldest daughter D.Maria.
However her position was threatened by the all-mighty PM, the marquess of Pombal.
He had ruled with an iron hand for decades with the king's aimiable compliance, establishing a hatred dictatorship.
He had persecuted all those who opposed to him, either in the Church - he casted out the powerful and influent Jesuits - and persecuted and tamed the aristocracy by whatever means - with the execution of their leaders the Duke of Aveiro and the Távora family, and condemning to prison many others, accusing them of being part of the attempted murder of the King.
The nobles that escaped from Pombal wrath formed the so-called second court around the then Crown-Princess Maria and her husband D.Pedro, in Queluz, who never hided their hate towards Pombal.
Pombal then forged a plan that consisted in overlap D.Maria and have her eldest son D.José succeed directly his grand-father and namesake king D.José I, on the grounds that she was a woman, ill-prepared, and would revert the reforms that Pombal had realized.
By that time, Pombal had taken the Prince of Brazil under his wing and made him a more enlightened prince rather than his pious and bigot family.
The King was ambiguous about that idea, but D.Maria harshly refused to abdicate in favour of her son.
Queen Mariana Victoria (of Spain), despite coming from a country where the Salic Law was applied, also opposed to the idea that her daughter would be disinherited and finally convinced her husband of cancelling such plan.
The Queen was also one of Pombal's great ennemies as she accused him of facilitating the king's many affairs.