A James Skinner and Jane Kewney were married in Cuyahoga County, Ohio, September 23, 1833 (from Cuyahoga County Marriage index, where she is indexed as "Keviney". See marriage record vol 3, p. 30. This is probably your James and Jane.

The 1850 census of Mishawaka Indiana indicates they were in Ohio when James 17 and William 15 were born, in Canada (do you know where?) when Sarah 14 was born, and in Indiana when Horatio 10, Mary 6, Lemote 4 and Florence 1 were born.

James may be the James Skinner in Newburg, Ohio in 1830, with 2 males 20-30 in his household (a brother, perhaps?)

I did not find James and Jane in 1860 or later. Where did they go?