However varied the reasons might be for the phenomenon, Frankenstein continually reverts
to the importance of documentary evidence to substantiate the truth of its events
or assertions. This will be seen as crucial in the case of the Creature's existence
and experiences (see II:6:7), of Victor's rectitude as a narrator (see III:WC:2),
even of Walton's day-to-day account of his voyage (likewise contained in letters "in
[his] own handwriting"). The pattern suggests that what is at stake here is the underlying
truth of all fictions.

This addition to the text seems motivated by a wish to make Margaret Saville a less
shadowy presence behind it. The implicit suggestion is that she is sufficiently older
than her brother to have cared for him when they were orphaned, though, considering
the twin facts that she has children in her own family and Robert is now 28 years
old, we must assume that the difference in age would amount to something like a decade
(III:WC:11). The added phrase also emphasizes the role of feminine nurturer assumed
by all the prominent women of the novel.

Age is always relative. Mary Shelley was some two months shy of her twentieth birthday
when she began writing Frankenstein and well past twenty-one when the novel appeared
in print. Moreover, before she began the novel toward the end of June 1816, she had
registered experiences highly unusual for a young woman in the constrained environment
of Britain, including eloping with a married man and twice giving birth. That said,
it is true that the author was in years yet an adolescent when she wrote this novel
and that, historically speaking, most of its readers have been struck by a range of
knowledge, maturity of conception, and intellectual ambition unusual in one so young.