Well after the 1861 census that shows a corrected name from Lamar Brown to Tamar Brown, which may or not be the correct family, there is also a 1881 census that has the correct name (Tamar) and also shows Jane Brown b: 1833 and again George b:1851 born in Ousby, Cumberland, living in Lancashire.
So if I can find her marriage to Brown this might start to look possible (maybe), providing her maiden name is listed as Clapperton that is.