The name Fanny (and similar names like Fanya and Fani) is a newcomer.
We have a relatively complete set of birth records for Nezhin Ukraine
1860-1918. The first Fanny is born in 1891; there are 6 total in the 1890s
(out of roughly 2500 births), more in the decade 1900-1909; and even more
in the period 1910-1918, even though the total births in the latter period
has shrunk to about 1400.
By contrast, girls are named Feiga throughout the 59 year period.
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