Griffiths Valuation for Cork was taken between 1850-1853.
Griffiths Valuation was basically a record of those holding or renting land property at the time.
Due the the fact that her father George Barry was a labourer probably means he may not be listed on Griffiths.
Also Griffiths only listed the head of house.
You can view Griffiths on this link
http://griffiths.askaboutireland.ie/gv4/gv_family_search_form.phpThe fact that he was a labourer may mean he had a very small amount of property rented.
I had a look on the LDS site and found three deaths for George Barry's born before 1827 according to their death cert assuming the father had the be at least twenty having Elizabeth Barry in 1847.
http://pilot.familysearch.org/recordsearch/start.html#p=homeThey are as follows, registration for Catholic deaths were taken from 1864 onwards.
George Barry born 1824 died Jul-0ct 1882 Cork Registration District
George S Barry born 1826 died Jan-Mar 1894 Kinsale Registration District
St. George Ryder Barry born 1792 died 1864 Cork Registration District