Hi there JoeJoe
I think that this is the right family for you.
As far as I know:
Cecil Albert de Lautour is the son of Edward de Lautour (born 9 Nov 1813 Westminster, London, d 16 Nov 1862 Cheltenham, Gloucstershire, England) and Catherine Sconce (b 19 Dec 1813 Sterling, Scotland, d 18 Sep 1899 South Kensington, Middlesex). They were married 1836 in Calcutta and had lots of children.
Edward de Lautour is the son of Joseph Andrew De Lautour (b 17 Apr 1785 Madras, d 28 Apr 1845 Hexton Park, Hexton Hertfordshire) and Caroline Young (1793 Soho, London, d 26 Nov 1869 Hexton Park, Hexton Hertfordshire).
Joseph Andrew De Lautour is the son of Joseph Francis Louis Lautour (commonly called Francis b 1752 Hexton Park d 26 Mar 1803 Devonshire Place, Marylebone, Middlesex) and Ann Hordle (b 1747 Wareham, Dorset, d 31 Oct 1825 Hexton Park). Joseph Francis Louis Lautou and Ann Hordle marry in 1780 in Madras.
Joseph Francis Louis Lautour in the son of Count Francois Lautour and Barbe Ruhn.
Joseph Francis Louis Lautour arrived in Madras in 1777.
Hope this is of some help.
I'm working on the theory that the Louis Latour in my family tree may be related to this family, based in the info posted above that Joseph Francis Louis Latour had an illegitimate son before his marriage to Ann Hordle. The ship 'Juno' that the illegitimate son was captain of was part of the East India Company fleet and was registered in Calcutta, which could potentially place any of his children (and possible my Louis Latour) in Calcutta. There are a few other stray Lautour/Latour etc in Calcutta. It is very difficult to work out how they all fit together or not, and whether thay are part of the De Lautour of Hexton Park or anther Latour family.
I have also found the baptismal records of a Mary Latour on 5 May 1778 at St John's Church Calcutta, daughter of Francis Latour. Interesting - I can find no other mention of another Francis Latour in Calcutta or India and assume that this could be anotherpossible illigitimate child Joseph Francis Louis Lautour (commonly called Francis).
I have worked out that Chery Manuel Latour (a Calcutta Hotellier) has at least 7 children, one Evelina Caroline Sarah Latour marries Arthur Dodd Walwyn Radcliffe in 1850 Calcutta. This marriage is witnessed by a William Bernard Carbery who married a Sophia Elizabeth Latour in 1831 Calcutta. These 2 Latour women must be related but I'm not sure how - possible sisters or aunt and niece.
I'm hoping if I can work on all the LATOURs in Calcutta I might find a connection to my Louis Latour.
Good Luck with your research
Regards, Perks1