Birth calculations 1850 - b. 1819

In the will of Jacob Brown II, Mary is mentioned as his step-daughter, Mary Cloyd. This confused us for a long time. A group of us did research on this Mary Cloyd and soon found that Mary Cloyd was actually a Salts -daughter of Mary "Polly" Salts. We have now identified that Mary was raised by her step-father, Jacob Brown, and then married under the surname of Brown to John Patton Cloyd. So it looks like she used her adopted father's name when she married.

Mary "Polly" Salts's daughter Mary married John P. Cloyd. Jacob Brown called her his "stepdaughter," meaning he was not her father, but she must have gone by the name Brown all her life.   All the things we have seen from 'way back have said her mother was a "widow with a daughter, Mary" and married Jacob Brown II 7 May 1816.  
 
What we have never known is whether she was born a Salts or married a Salts.  We still don't know that. If she was married to a Salts and then widowed, there was a male Salts we don't know who died sometime around 1814-15, since Mary married Jacob Brown 7 May 1816 and the baby Mary had to be born before or around that time. In that case, we would not know what her maiden name was.
 
But she might have been Mary "Polly" Salts by birth and had the baby Mary illegitimately and then married Jacob Brown II.  This tree that you sent shows that the baby was called Brown -- formally adopted or not. That helps.  
 
Here,  I have turned the tree upside-down because that is the way I think.  Compare it with Sam's 1850 census message and we can get the children of the Cloyd-Brown marriage.  Mary died before 1860. 
 
Generation 1:
Father: William Cloyd b: 1751 in Ulster Province, Ireland
Mother: Jeanette Barr b: 1753 in Ulster Province, Ireland

Children

James Barr Cloyd b: 25 DEC 1779 in Philadelphia, Pennsylvania
Jeanette Cloyd b: 17 JAN 1784 in Philadelphia, Pennsylvania
Sarah Cloyd b: 26 MAR 1777 in Philadelphia, Pennsylvania
Samuel Cloyd b: 25 DEC 1781 in Probably Virginia
William Cloyd b: 22 MAR 1786 in Washington County, Tennessee
John H. Cloyd b: 17 MAY 1793 in Washington County, Tennessee
Margaret Cloyd b: 14 AUG 1795
Mary Elizabeth Cloyd b: 22 MAR 1788 in Washington County, Tennessee
Generation 2:
 
Father: James Barr Cloyd b: 25 DEC 1779 in Philadelphia, Pennsylvania
Mother: Mary Patton b: 27 OCT 1780 in Hamiltonban Twp., York (now Adams) County, Pennsylvania
Married: BEF 1807 in Washington County, Tennessee
 
Children

Jane "Jennie" Barr Cloyd b: 2 JAN 1807 in Washington County, Tennessee
John Patton Cloyd b: 29 JAN 1809 in Washington County, Tennessee
James Barr Cloyd b: 13 JUN 1823 in Washington County, Tennessee
Elizabeth Cloyd b: 9 JAN 1814 in Washington County, Tennessee
William Cloyd b: 18 JUN 1817 in Washington County, Tennessee


Generaton 3:
John Patton Cloyd
Sex: M
Birth: 29 JAN 1809 in Washington County, Tennessee

Marriage 1 Mary Brown
Married: 30 MAR 1837 in Washington County, Tennessee
Washington County marriages 1835-1837
John Cloyd --Mary Brown --Mar 30 1837 

1850 census 
CLOYDE, John P. 42 TN
CLOYDE, Mary A. 31 TN
CLOYDE, Mary J. 12 TN (b. 1838)
CLOYDE, Elizabeth 10 TN (b. 1840)
CLOYDE, James B. 8 TN (b. 1842)
CLOYDE, Sarah 6 TN (b. 1844)
CLOYDE, Enos C. 2 TN (b. 1848)