These are Maughold families. Bill and Constance Radcliffe in their History of Kirk Maughold p. 343 write: "Robert Oates Christian was a member of one of the most ancient and distinguished Ramsey families, the French Christians, formerly of the Flatt. R. O. Christian himself had been in business in Le Havre before retiring to Ramsey.” The site of the Flatt is now in the middle of the town, near the terminus of the Manx Electric Railway. There is more in Constance’s Ramsey 1600-1800, p. 117.
Robert Oates Christian (1795-1867) is buried in Maughold churchyard, in grave 211. One of his sons was Thomas Philip Christian (1830-1897), buried in grave 122 with his son Thomas Philip (1882-1889).
Robert Edward Christian was from the family of Christians at Baldromma, near Maughold Head. There were three Robert Edward Christians in successive generations. Robert Edward (1817-1891), a sea captain and Manx scholar, is buried in grave 27. His son Robert Edward (1855-1890) was also a sea captain, and died unmarried, buried in grave 26. His brother Howard Alfred Christian had a son Robert Edward, b 1901, d in infancy.
Which Robert Edward are you interested in, Elaine? I don’t know of any connection between these two Christian families. Perhaps a member of one owed a member of the other some money at the time of the death.