Mary, who, since her betrothal, had been taught to consider herself as the future bride of the emperor, was at the time but eleven years old. She was old enough, however, to feel something like jealousy, it is said, and to show some pique at this desertion by her imperial lover. Yet this circumstance did not prevent the most friendly relations from subsisting between the parties in after years; and Charles continued to watch over the interests of his kinswoman, and interposed, with good effect, in her behalf, on more than one occasion, both during the reign of Henry the Eighth and of his son, Edward the Sixth. On the death of the latter monarch, he declared himself ready to assist Mary in maintaining her right to the succession;[62] and, when this was finally established, the wary emperor took the necessary measures for turning it to his own account.[63] He formed a scheme for uniting Philip with Mary, and thus securing to his son the possession of the English crown, in the same manner as that of Scotland had been secured by marriage to the son of his rival, Henry the Second of France. It was, doubtless, a great error to attempt to bring under one rule nations so dissimilar in every particular, and having interests so incompatible as the Spaniards and the English. Historians have regarded it as passing strange, that a prince, who had had such large experience of the difficulties attending the government of kingdoms remote from each other, should seek so to multiply these difficulties on the head of his inexperienced son. But the love of acquisition is a universal principle; nor is it often found that the appetite for more is abated by the consideration that the party is already possessed of more then he can manage.