Thank you so much Gadget - the birthplace will probably have been Jeddart. I was definitely confused by the tail from the 'g' above!
We think that these are the children, in order - John, George, Robert, Jessie (Janet), Walter, Helen, Thomas, Thomas, James, Jane, and Mary.
I'll look for the 1788 baptism in Kirkton.
The 1786 bap in Kelso to William and Isobel is unlikely to be my John, as the names are not in the family. There is a bap in Roberton 1788, father Robert Riddell, and one in Hobkirk 1784, father Walter Riddell.