Thanks all for your replies - sorry for delay in responding - seem to have been logged out and didn't get notified of your interest!
Yes lots of confusion on spellings, but I'm fairly certain Christiana Agnes is a Latour daughter of Louis Latour.
At marriage of Christiana Agnes and John Milne her father is listed as Lowis Latour. Seems to be other variations but Latour is the name that has come down the family in subsequent generations.
I have bad some luck now in putting most of this tree together and it all looks to fit quite nicely. Just trying to trace further back but as is a frequent story I have hit the dreaded brick wall!
Thanks again.