As I have been looking at the research done by others regarding the children of Elijah Rice and Sarah Riffe, I am finding Elijah's and Sarah's seemingly accepted dates of birth don't seem to fit the births of their children. As Sarah is usually listed as nine years younger than Elijah, this problem seems to rest more on her birthday's shoulders.
In nearly all reports I have seen, Sarah's date of birth is in 1796 and Elijah born in 1787. In much of the research that I have seen, Sarah has had her first child as early as 1798. She would have been two years old if this were true.
Assuming the 1820 federal census for Elijah Rice in Greenup County represents Elijah and Sarah, they most likely had eight children at that time. Three of which are 16 or older, making Sarah roughly five years old for the birth of the first one.
I apologize if this issue has been addressed before. I've looked around and I haven't seen any evidence that this has even been brought up until now.