Thank you Pam - the trigger words are "that sounds familiar".  A couple of months ago when I was trying to get some hold on Captain John – I checked the adresses he used in Liverpool. He had given these on his applications for mates and master’s examinations. I thought I might get a clue to his first marriage. Had he married the landlady’s daughter! Now we know better,
Now Pam's comments about half remembered names and recalling the link between Helen Elliot and Edward taking me back over old ground to blacksmiths, George and Thomas, I thought I might put here the occupants of the boarding houses – just in case names ring a bell for anyone.
CENSUS 1861                        
38  Sparling Street, Liverpool, St.Thomas         Ecclesiastical parish  St.Michaels               
   Relationship to   Where Born   Condition    Sex    Age    Profession/Occupation,      
Name     Head of H'hold                                              
CAMERON, Hugh    Head    Ireland                              M    M    60   Lodging House Keeper      
CAMERON, Margaret     Wife    Ireland                      M    F    50         
CAMERON, Mary            Daughter                     U       F    19   Domestic Servant      
CAMERON, Esther         Daughter    Liverpool   U     F    13   Domestic Servant      
CAMERON, Annie             Daughter    Liverpool   U    F    9   Scholar      
CAMERON, Hugh             Son               Liverpool      U    M    17   Sailmaker      
MC KENZIE, Donald     Son ‘Law    Scotland   M    M    28   Seaman Merchant Service      
MC KENZIE, Margaret    Daughter    Ireland            M    F    27   Seamans Wife      
MANSON, Daniel               Boarder        Scotland      M    M    31   Seaman Merchant Service      
HUIG, Henry                    Boarder    Holland            U     M    28   Seaman Merchant Service      
BROWN, William                Boarder         Ireland         U        M    30   Lab Sugar W’house      
BARNES, Thomas              Boarder       Bolton      U    M    23   Seaman Merchant Service      
When John qualified as master he moved “up market” to  Kent Square and stayed there during shore time, between Jan '60 - Jan '61. His marriage to Helen is in the Wirral: when I worked in Liverpool that was the posh side of the Mersey. Why did John not stay with his Shennan relatives ? Kent Square is just a couple of minutes from the docks - 

 But . . .
CENSUS 1861                     
13 Kent Square, Liverpool, St Thomas                     
   Ecclestical Parish  St.Marks                                       
Name     Relation ‘ to   Where Born    Con’dt   Sex    Age    Profession/Occupat’                        
BOWMAN, David    Head    Ireland     M   M    35   Joiner   
BOWMAN, Jane    Wife    Scotland     M   F    33      
BOWMAN, James    Son    Lancaster Walton On The Hill     Un   M    3      
BOWMAN, John    Son    Lancaster Walton On The Hill     Un   M    1      
CASSADY, Daniel    Boarder    Scotland     M   M    50   Master Mariner   
CASSADY, Robert    Boarder    Scotland     M   M    28   Master Mariner   
DUKE, James    Head    Sielly Isles   [sic]   M   M    34   Master Mariner   
DUKE, Mary    Wife    Sielly Isles   [sic]   M   F    30      
I get no results searching for Ann Shennan in the 1841 and 1851 Census. The area of UK with the highest concentration of the name Shennan,  in both 1881 and 1998, is Dumfries. Why does the gravestone list Ann as “Scott” Shennan? Was she really a Scouser ? I think Ann’s family were from “back home” in the Annan area. But I am not going to try to compete with Jo in the intuition department.