Hi Yonks Ago
I have been researching the same Langdon line as you - Elizabeth Langdon, daughter of John Nicol & Louisa (nee Smith) Langdon, is my great-grandmother.
I wanted to let you know that I think I have had a break-through on Louisa Smith's maternal line, the Bulgers. Here's what I have;
A newspaper article on Trove, from The Horsham Times, 13 Jan 1885, lists a case between Rose Boyd and Louisa Langdon (Langdon is broken by the text transcription into "Langd m", so won't be picked up by a search for "Langdon"). It states that they are cousins, and Rose was in the company of "Albert Langdon, defendant's brother-in-law", and mentions him later as "Johnny's brother" - both facts confirmed by our family tree research.
I searched for "Rose Boyd" in other articles, and found another (1874) listed with her mother Maria - hoping this might be the same girl (Rose), and given that Rose and Louisa were listed as cousins, I searched Vic BDM for a Maria Smith or Maria Bulger marrying a Boyd, and found that a Maria Bolger married a George Boyd in Melbourne 1852. In addition, Maria's death cert (1883), lists her father as Richard Bolger, and her birthplace as Kildare.
So, I have assumed that Maria Bolger is Jane Bulger's sister - perhaps a weak link, but in searching further for children of Richard Bolger in Australia, I have found Matthew Bolger (1828-1876), who had a daughter Catherine Elvina Bolger (1862-1939), who I feel is surely related to Jane's daughter Elvina Kate Smith (1852-1853), given the unique names.
I have expanded the families, and feel sure that Jane's family name is BOLGER, her father is Richard, a sawyer from County Kildare, her mother's name is very possibly Catherine (Kate, perhaps Higgins), and she had another sister, Louisa Bridget (~1839-1882), who could be the Bridget Louisa Bulger on Jane's marriage cert. to Thomas Smith.
Anyhow, lots for you to look through, and would be good to see if you agree with the links?
Regards
Zep