Cheryl - Not too many bells other than those related to the given names of Wm and Rbt. The reported patriarch of the IL clan was bn ENG prior to 1776, and likely arrived in the US prior to that tame, establishing a shipping trade along the East and Gulf Coasts. He had at least 2 children, perhaps 3 or 4. Some claim he moved to OH, then IL, others say he did not make it to IL. Two of his children were Wm and John.
William ALLEN was likely born prior to 1790, possibly in GA. It is believed he had at least two children, John M ALLEN, and Catherine (ALLEN) NORTH, both born OH, likely Preble CO, and both born around 1810 or before. William is said to have moved his family to IL ca 1814, and he died ca 1840 in the vicinity of present day Evansville, Randolph CO, IL. I have yet to identify his wife's name.
John R ALLEN, son of Robert and brother of William, likely was also born prior to 1790, at least by 1795. He married Miss Sarah ALLEN (no known relatiosnip), presumedly in GA. I have only limited data on John's line, but it appears his first child was born in late 1810.
At first glance, then, I cannot see a link between the Wm ALLEN of my interest, and those in GA during the 1830s.