Richard Slack was a widower when he married Margaret G, both of Wetheral parish and the witnesses were Jane Young and Thomas Dixon.
The gap in Wm/Mary's children is curious, but maybe some of their children were baptised in Carlisle.
And I'm glad that it wasn't that Wm/Mary who died in the workhouse

I've no idea whether any of the Grahams in the censuses were distant relations, because our G male ancestor moved from Wetheral in 1797. But the Wetheral connection continued for another century, because he inherited a lot of tenanted land and houses (copyhold/customary) in Wetheral, which were passed down to the eldest son in each succeeding generation.
There was also a family connection to Eden Brows/Froddle Crook, which belonged to one of our Graham ancestors (a g/g/g/g/uncle) and was inherited by his son, who was there in the 1841 and 1851 censuses, but died before 1861.