Fr. John Hardon (a Jesuit of the 20th century with all the expected baggage) on the Immaculate Conception. These objective facts are not in question:

We might note here that Pius IX, who defined Mary’s Immaculate Conception, had been an epileptic. Even though he had severe seizures he was allowed to remain on at the Seminary, but was told he could never be ordained. He prayed and begged Our Lady to cure him of epilepsy. For some time before the perspective ordination he had no seizures. The then Pope intervened and reluctantly allowed him to be ordained, under one condition: that he would never offer Mass alone, but would always for the rest of his life have a Priest next to him in case during Mass he would have another seizure. Now as a Priest he prayed: “Mary, no more seizures, please. Also, would you please spare me the embarrassment and inconvenience of never being allowed to offer Mass without another Priest at my side.” For several years he continued offering Mass with an assistant Priest, no seizures ever occurred. Finally, the Holy See withdrew the condition and (the future) Pius IX vowed that he would spend the rest of his life doing everything in his human power to advance Mary’s honor. On the day he proclaimed the dogma of Mary’s Immaculate Conception, Pius IX declared that this was the happiest day of his life, his opportunity to repay Mary for what she had done for him.