Jane,
Yes, the Kingston University site is where we found that Ursula was buried in the same cemetery as John - previously we only knew of her burial service at All Saints Kingston but couldn't find a grave there. Also, the birth you found of John Q3 1844 is the ninth and youngest child of John and Ursula that we know of.
Sue,
The problem we have with the Robert/Hannah marriage is that neither of these names are in any of the subsequent families. However, we have to try to find whether they had a son John around 1800 - 1805. There are other instances of Luxton/Coles marriages in Devon; William Luxton son of John Luxton and Ann Down had a second marriage to a Mary Coles on 10 Jan 1824, ref correspondance with Brian Luxton.
Michael J.