Pietro therefore determined to defer his departure; and the Cardinal, when he heard his reasons for doing so, fully approved of his remaining in Florence, till they could have an opportunity of consulting together on the subject. This was furnished them early in the following year, 1586, on the occasion of the marriage of Virginia de' Medici, the daughter of Cosmo by his wife Camilla de' Martelli, with Don Cesare d'Este. Virginia was thus half–sister to Francesco, Ferdinando, and Pietro, and the Cardinal was to come to Florence to be present at the ceremony. The marriage was accompanied by more than usual splendour. But the only circumstance that excited[211] the interest of the Florentines in the matter, was to see their old Grand Duchess, poor Camilla Martelli, still very beautiful, appearing once again among them, as if risen from the grave. Francesco had permitted her to come out from her nunnery prison, in which he had kept her now twelve years, to be present at the marriage of her daughter. And all Florence was disgusted and astonished, as far as any fresh atrocity on the part of Francesco could astonish it, when the unhappy lady was, at the conclusion of the ceremony, compelled to return to her cell. Ferdinando, who had frequently endeavoured in vain to induce his brother to mitigate the rigour of her imprisonment, was much angered by this new cruelty. His disgust was increased by the Duke's curt refusal to lend him any money; and he returned to Rome with feelings as hostile to his brother as they had ever been; but not before he had arranged with Don Pietro that he should remain in Florence to watch the proceedings of Bianca and the Grand Duke. The Cerreto event was rendered much more important in their eyes, by the circumstance of the Duke's having, by a formal circular, announced the pregnancy of the Grand Duchess and its unfortunate termination to all the friends and connections of the family. Of what use was it, they asked, to publish the news of a misfortune of such a nature? Evidently it was intended only to keep alive in the minds of those addressed, the expectation that Bianca might have another confinement, and thus prepare the way for a new fraud. To guard against this was, as the Cardinal felt, paramount to all other considerations. Anxious, therefore, as he had been that Don Pietro should proceed to Spain, to conclude the arrangements for his own marriage, he judged it yet more important that he should for the present remain at Florence. And it was not long before the suspicions, which had dictated this surveillance, were justified by the event. In the April of 1586, reports began to be spread that the Grand Duchess was again pregnant. And on the 15th of that month Don Pietro wrote to the Cardinal as follows:—[212] [Sidenote: PIETRO'S LETTER.]