sammarland on Family Tree Circles

Moses Land was born in South Carolina and made it to Garrard Co, KY to wed Catherine Ann Warren (1807-1834) on 20 Apr 1822.I have a copy of the marriage license. The 1830 Census indicates that Moses had an all white home to include:
James Land 0-1 yr old
William Perry Land 3
Joseph Land 8
Moses Land 28
1 Under 5 female
Catherine Ann Land 23

Total 6 persons.

Ann warren died at the age of 28 in 1835. Moses married Elizabeth Wells 1805-1854) on 23 Jul 1840. The 1850 census (which now provides the names) indicate the people at home to Moses as:

Moses 46
Elizabeth (Wells) 45
Moses 17
Richard 14
Samuel 13
John H 12
James 11
Elijah 10
Peter 9
Newton J 7
George W 4
Zachary 3

Joseph Land 58 (Joseph is Moses' Uncle -John Land's son- and Joseph died in 1850 evidently living at Moses' home.) Who is the unknown female child in 1830? How can it be proved that Moses is William Perry's father?

Samuel Land 1510-???? England
Thomas Samuel Land 1546-1648 England
William Land 1571-1647 England
Thomas Land 1614-1687 England
Samuel Land 1652-1687 England/Delaware
John Land 1675-1730 Delaware
Joseph Alexander Land 1724-1803 Delaware/South Carolina
John Land 1756-1849 Virginia/Kentucky
Moses Land 1792-1882 South Carolina/Indiana
William Perry Land 1827-1879 Kentucky/Indiana
John Anderson Land 1847-1915 Indiana
Charles Perry Land 1880-1970 Indiana
Virgil Leroy Land 1823-1981
Sammy Leroy Land 1945 - living

If you want to chat about any of this I am most willing. If you believe that I have errors, please let me know what they are and what they should be. I will try to help you, too, if you have questions about this line.

Sam

I am rather stuck and I would appreciate your help. I have attempted to prove my family line to the satisfaction of the SAR (Sons of the American Revolution.) I have a point that seems not provable. William Perry Land (1827-1879) should be the son of Moses Land (1792-1882) but I can not prove it. They lived very close to each other through their lives and they are buried in the same cemetery. Unfortunately, Moses died intestate and I can not locate any obituary for him or statement that mentions William Perry as his son. In the 1840 census Moses has an amount of children that would make him the oldest son sill living at him but in 1850 when names were first provided, William Perry has moved out on his own. Does anyone have any information that might help and can suggest a way to discover the truth. I must add that I did hire a professional genealogist from Decatur County, Indiana, and he could not find any documentation.