surname isn't spelt that way but I'll have a gander
Don't get hung up on spelling. You may spell it in a particular way now, but your ancestors were not so fussy.
One of my great-great-grandfather's sisters married a William Stewart in 1850. His surname is spelled in different ways - in his marriage record it is Stewart and in the baptism of his eldest son six weeks later it is Stuart - and so are those of his family. Spellings became more fixed about the beginning of the 20th century, but some of his descendants now spell it Stuart and others Stewart.
I have no ideas on dates as I can't seem to find anything on and family tree site.
Are you looking on the right sites? See
http://www.rootschat.com/forum/index.php?topic=714261.0Once you have looked at the 1872 marriage certificate at
www.scotlandspeople.gov.uk you will know the names of both John's and Jessie's parents.
According to FamilySearch
www.familysearch.org John and Jessie had at least three children
James born 21 December 1869 in Inveravon, Banffshire
Unnamed daughter born 26 February 1873 in Glasgow Blythswood (probably died in infancy)
Ann born 17 March 1874 in Glasgow Bridgeton
The 1881 census says that John and Ann were born in the parish of Kirkmichael, and that James and George were born in Glenlivet. There is also a housekeeper, Ann Sharp, aged 42, born Glenlivet. I wondered if Jessie might perhaps be in hospital, but I can't find her.
Note that the family is in Laggan
in the parish of Inveravon. There is a parish of Laggan in Badenoch in Inverness-shire, and the Laggan Locks on the Caledonian Canal in the parish of Kilmonivaig, as well as umpteen other Laggans that haven't sprung to mind. If you look for Laggan on any map at a smaller scale than 1:50,000 you will not find the right place.
See
http://www.geograph.org.uk/gridref/NJ2026 for a map showing your Laggan. It's near Blairfindy and The Glenlivet Distillery.
This
http://maps.nls.uk/geo/explore/#zoom=15&lat=57.3253&lon=-3.3129&layers=5&b=1 is your Laggan on the mid-Victorian Ordnance Survey map.
It's impossible to stress enough how essential the
parish is for any genealogical research outwith the major cities until the mid-20th century.