Good points SelDen.
I am taking the roundabout route and following nephews and nieces. The name Lancelot is seen again with Norman Lancelot Brown (1903-1966), who is related to Lancelot Brown (1757-1822).
Two of William and Isabella's children are staying with Isabella's brother Thomas Brown in 1851. Possibly because it's a more stable environment as Thomas is a farmer and better off than William, a shepherd.
The Laidlers and the Browns appear to have lots of ties. I'm filling in a lot of blanks with my Ancestry tree to see what crops up.
Thanks
Richard