From FamilySearch:
John SOUTHALL (23), son of John SOUTHALL, married Jane DUGGAN (19), daughter of Joseph DUGGAN, 24 Sep 1862, St Andrew, Bordesley.
From earlier censuses, Jane was born Aston/Birmingham.
Nelly's birth is the only one to this couple on FamilySearch. ("Nellie" on her birth reg.)
I haven't spotted an obvious match on census after their marriage, so I wonder whether one or both died pre-1871?
Rambler