Georgina Shearmur's sister

This one was clearly labelled on the back "Georgina Naish's sister" Well she had 5 sisters. The photographer for this one was R Ward 10 Eastgate Rd Gloucester Gloucestershire and  was in business from 1862 to 1870. (1)

How old do you think she is ? My guess is about 20-25 years old.

Which of the sisters is it?

Frances Elizabeth was  born in  1835 and died in  1854 so it is not her as she was not alive when the photographer practiced.

Mary Ann was born in  1837 and married in 1871 in Chipping Sodbury, Gloucesterhire, UK so it could be her if the photo was taken early in the business lifespan.

Arlette was born in 1840 and married in 1861 in Bethnal Green, Middlesex, UK  so it is probably not her.

Jane was born in 1847 and married in 1872 in Chipping Sodbury so it could be  her as she would have been 20 in the middle of the business lifespan.

Elizabeth Margaret  was born in 1850 so it could be her as she would have been 20 at the end of the business lifespan.

From the site http://freepages.family.rootsweb.ancestry.com/~victorianphotographs/date/main.htm the clothing dating photos suggest 1866-1868. So my deduction is that this is Jane Shearmur.
Do you agree?

(1) http://www.victorianphotographers.co.uk/index.php?searchStr=ward&_a=viewCat&page=5