In the 1901 census Dorothy's birthplace is given as 'Metal Bridge' (I haven't seen the original image).
What about this family in 1891
RG12/ 4055/ 121/ 5
Sharps Buildings, Cross Row, Cornforth
Thomas Storey, head, m, 28, coal miner, Northumberland, Bankfoot
Elizabeth Ann Storey, wife, 23, Durham, Evenwood
Dorothy Storey, daur, 4, Durham M?? Bridge (with the eye of faith it could say Mettle Bridge)
Thomas Storey married Elizabeth A. Richardson, 2nd quarter 1885, Stockton 10a 73
Jennifer