Her prospects in England were still further improved when she gave birth to a son (June 19, 1566). Once more there was an heir-male to the old royal line, and, as Elizabeth continued to evade marriage, most people who were not fierce Protestants began to think it would be more reasonable and safe to abide by the rule of primogeniture than by the will of Henry VIII., sanctioned though it was by Act of Parliament. There can be no doubt that this was the opinion and intention of Elizabeth, though she strongly objected to having anything settled during her own lifetime. But she had herself gone a long way towards settling it by her treatment of Mary’s only serious competitor. Catherine Grey had contracted a secret marriage with the Earl of Hertford, son of the Protector Somerset. Her pregnancy necessitated an avowal. The clergyman who had married them was not forthcoming, and Hertford’s sister, the only witness, was dead. Elizabeth chose to disbelieve their story, though she would not have been able to prove when, where, or by whom her own father and mother had been married. She had a right to be angry; but when she sent the unhappy couple to the Tower, and caused her tool, Archbishop Parker, to pronounce the union invalid and its offspring illegitimate, she was playing Mary’s game. The House of Commons elected in 1563 was still undissolved. It was strongly Protestant, and it favoured Catherine’s title even after her disgrace. In its second session, in the autumn of 1566, it made a determined effort to compel Elizabeth to marry, and in the meanwhile to recognise Catherine as the heir-presumptive. The zealous Protestants knew well that the Peers were in favour of the Stuart title, and they feared that a new House of Commons might agree with the Peers. To get rid of their pertinacity Elizabeth dissolved Parliament, not without strong expressions of displeasure (Jan. 2, 1567). Cecil himself earned the thanks of Mary for his attitude on this occasion. It cannot be doubted that he dreaded her succession; but he saw which way the tide was running, and he thought it prudent to swim with it. It was at this moment that Mary flung away all her advantage, and entered on the fatal course which led to her ruin. Her loathing for Darnley, her fierce desire to avenge on him the insults and outrage she had suffered, left no room in heart or mind for considerations of policy. She would have been glad to obtain a divorce. But the Catholic Church does not grant divorce for misconduct after marriage. Some pretext must be found for alleging that the marriage was null from the beginning. This did not suit Mary. It would have made her son illegitimate, and would have placed her in exactly the position of Catherine Grey. A mere separation _a toro_ would not have suited her any better, for it would not have enabled her to contract another marriage.