Hello again,
David and Jacobina had 7 children (as far as I know). They were -
James (your grandfather)
Janet b. c1857
John b. c1858
David c. v1860
Mary Ann b. 1863 She married a William Gilchrist and they had 3 children: William C Gilchrist b. about 1898, Mary H Gilchrist b. about 1900, and David Grierson Gilchrist 1903-10/09/1937. In 1901 the family was enumerated living at 37 Bank Street, Dumfries with 2 oldest children. Her husband was a grocer.
Elizabeth b. c1867
Edgar b. c1871 (enumerated in 1891 census. age 19, living as a Boarder at 234 Cumberland St, Govan, Glasgow. Job title Engine Fitter's Labourer.
Children's names found in various census records. Additional info - in 1861 & 1871 David and Jacobina were living at Piehills (aka Pyehills), Ruthwell, where David was working as a Shepherd and then as an Ag. Labourer.
In the 1881 & 1891 census records, David and Jacobina have moved to Station Cottage, Kirkgunzeon and David is described as a Railway Surfaceman.