From St. Gregory the Great's biography of St. Benedict, the brother of St. Scholastica:
The worshipful Scholastica, the sister of our Father Benedict, was hallowed unto the Lord Almighty from a child. Her custom was to come to see her brother once every year. And when she came, the man of God went down unto her, not far from the gate, but, as it were, within the borders of his monastery. And there was a day when she came, as her custom was, and her worshipful brother went down to her, and his disciples with him. Then they passed the whole day together, praising God, and speaking one to the other of spiritual things. And when the night came, they brake bread together. And while they were yet at table, and conversed together on spiritual things, the hour was late. Then the holy woman his sister besought him, saying Leave me not, I pray thee, this night, but let us speak even until morning of the gladness of the eternal life. He answered her: What is it that thou sayest, my sister? I can by no means remain out of my cell. Now the firmament was so clear that there were no clouds in the sky.
Then the holy nun, when she had heard the words of her brother, that he would not abide with her, clasped her hands on the table, and laid her face on her hands, and besought the Lord Almighty. And it came to pass that when she lifted up her head from the table, there were great thunderings and lightnings, and a flood of rain, insomuch that neither the worshipful Benedict nor the brethren that were with him could move as much as a foot over the threshold of the place where they sat. Now when the holy woman laid her head in her hands upon the table, she wept bitterly, and as she wept, the clearness of the sky was turned to a tempest. As she prayed, immediately the flood followed. And the time was so, that she lifted up her head when it thundered, and when she had lifted up her head, the rain came.
When the man of God saw that he could not return to his monastery, because of the lightnings, and thunderings, and the great rain, he was sorrowful and grieved, saying Almighty God forgive thee, my sister; what is this that thou hast done? She answered him Behold, I besought thee, and thou wouldest not hear; I besought my God, and He hath heard me; if, therefore, thou wilt, go forth, leave me alone, and go thy way to thy monastery. But he could not, and so he tarried in the same place, not willingly, but of necessity. And so it came to pass that they slept not all that night, but fed one another with discourse on spiritual things.
And when the morning was come, the worshipful woman arose, and went unto her own cell, and the man of God went back to his monastery. And, behold, after three days he was sitting in his cell, and he lifted up his eyes to heaven, and saw the soul of his sister, delivered from the body, fly to heaven in a bodily shape like a dove. Wherefore he rejoiced because of the glory that was revealed in her, and gave thanks to Almighty God in hymns and praises, and made known to the brethren that she was dead. He commanded them also to go and take up her body, and bring it to his monastery, and lay it in the grave which he had made ready for himself. Whereby it came to pass that they twain who had ever been of one mind in the Lord, even in death were not divided.