In 1830 Moses Copeland was reported in Covington County MS. On Dec 19, 1835, he married Elizabeth Edwards in Washington County AL. On the census of 1840 and his family are living in Mobile. Without a fair amount of time and effort to identify all his children, I would not guess at the relationship of either Moses Copeland to anyone else. However, since the 1850 census shows three girls plus Moses in the household of Moses and Elizabeth Copeland, and the 1830 census lists several children, we can assume that Moses had older half brothers and sisters from his father's first marriage (ca 1810).