I have the following family on 1871 census living in Shotton, Easington but cannot locate them anywhere after this.  I wondered if they might have emigrated.  Can anyone help me find them?  
William Parkinson, head, 26, coalminer, born Walker, Northumberland  
Ann Parkinson, wife, 34, born Washington, Durham
George W Parkinson, son, 3, born Shotton, Durham
Edward Parkinson, son, 1, born Shotton, Durham  
Thanks!
Foffie