Riley Familiy Early 1800s in Alabama

Hi All, 

This is my first post. I am researching the Riley family in Alabama in the early 1800's. My g-g-great grandfather Milton Riley was born in South Carolina around 1813 and died in Mississippi around 1900. Or, may also died in Buena Vista, Monroe Co. Alabama after 1900 but before 1910. However, he lived most of his life in Tuscaloosa Alabama. 

I think I have hit a brick wall when I look for his parents and siblings. I think he  father was William Riley, but there are many, many, William Riley's living in Alabama at this time that may be his father. I have been trying to find a will or probate records of any William Riley to see if he had a son by the name of Milton. I have not been able to find any so far. 

I know Milton married Mary Cook (1820 - 1904) on 19 Jan 1838 in Sumter Alabama. 

Dose anyone researching the Riley family in Alabama have a Milton in your tree? Or, does anyone have any advice about how I can break through this brick wall?

Thanks!

Brian