James Paterson

I am trying to find information about James Paterson who could have possibly been the brother of John Paterson who was born in Leith, Midlothian, Scotland around 1792.James went to Ontario West, Canada sometime before the 1851 Canada Census and settled in Bentinck Township, Grey County, Ontario West.His wife was Margaret (possibly Osborn).He had two sons that I know about in Scotland - Robert born about 1825 and William born about 1828...so they would have had to left Scotland between 1828 and 1851.Anyone have any ideas or thoughts?I'd appreciate them!