Under what circumstances did Dr. Manette see Charles Darnay as a small child?

At the end of Chapter XIX of Book the Third, Monsieur Defarge produces a piece of paper that he found when he entered the Bastille on the first day of the Revolution. This piece of paper is from 105 North Tower of the Bastille prison; it is the personal record of Dr. Alexandre Manette. Ironically, his writing of this record turns out to work against Dr. Manette's defense of Charles Darnay in his second trial, for in this paper, Dr. Manette denounces the entire Evremonde family.

During the reading of Manette's record, it is revealed that the Evremonde twin brothers had caused the death of a family except for a younger sister who had been taken to safety. A young man whom Dr. Manette had been summoned to attend placed a blood curse upon the Evremonde family before he died; his ravished sister died shortly afterward. Worried about the consequences of their actions, the Evremondes had Manette taken to prison. Because of his unjust imprisonment, Manette condemns the Evremondes.

In the contents of his written document, Manette made mention that the wife of one of the Evremonde twins paid him a visit on the following day after somehow learning of the deed, although she was unaware that the girl had died. She told Dr. Manette that she was in dread of the brother and her husband both.

"I have a presentiment that if no other innocent atonement is made for this, it will one day be required of him."

Then, she kissed the boy with her, saying, "It is for thine own dear sake. Thou wilt be faithul, little Charles?" This boy, of course, is Charles d'Evremonde, who has changed his name to Charles Darnay.