That's interesting, I wonder why they are not on line anywhere else, I did wonder what the occupation of the father was, at this moment I can't find Frederick Henry or Louisa Emily, Harriet's parents on 1841, it did occur to me there might be a foreign connection and Harriet had married abroad, but not so as you have found them, I cannot find her on 1861 with her mother either, father was already deceased.
Parents married 1838 Lambeth , Frederick Henry Colepepper and Louisa Emily Thompson
Looks as if you have solved the problem so I will back off
LM
PS father shown on Harriet's bapt as a mariner, Charles St Walworth Southwark