Mary Ann Dean was born in Kent Co., DE on 26 May, 1852. She was the oldest child of Robert Dean and Catherine Morgan .

Sometime before 1872, she married Moses Coker and they had the following children :

1. Selenar Coker (born 6 Aug. 1872- died before 1923)
   
2. Mary Eliza Coker (born 13 Aug. 1873- died before 1923) married Cassius MOSLEY
   
3. Robert James Coker (1874- died after 1957) married Nellie Miller
   
4. Andrew Coker (born 28 March, 1876 - died before 1923)
   
5. Lucinda Coker (born 15 Sept. 1877-died before 1923)
   
6. Albeda Coker (1878-1953) married Cassius MOSLEY and Calvin CLARK
   
7. Sadie J. Coker (born 14 Jan. 1881- died 15 Dec. 1957) married William Washington
   
8. Angie Bell Coker (1882- 1937) married Andrew MOSLEY
   
9. John Clayton Coker (1884-1915) married Phoebe CARNEY
   
10. Moses Elwood Coker (b. 15 Feb. 1886) married Margaret MORGAN
    
11. Catherine Coker (born 27 Feb. 1888- died before 1923)
    
12. William H. Coker (1889-1965) married Lillie Mae SAMMONS
    
13. Amanda E. Coker (1891-1963) married Clem CARNEY
    
14. Daniel Coker (born 12 May, 1893- died before 1923)
    
15. Nathan Louis Coker (born 5 Dec. 1894-died 1955) married Anna MOSLEY
    
16. Caroline Coker (1896-1981) married Levin Jackson
    

After the death of her father in 1874, Mary Ann Dean and her husband Moses Coker supervised the sale of the old Dean family farm located along the "old Dover to Smyrna Rd." which had been passed down from James Dean to his great grandson, Robert.

Mary Ann died on 21 November, 1923 at 11:30 PM on a Wednesday night, at the home of her daughter, Amanda Coker Carney. For nine weeks she had struggled with what was thought to be a temporary indisposition before dying. Her death certificate lists her race as "Moor", her age as 69 years, 6 months, her mother's maiden name mistakenly as "Coker". The undertaker was, as expected, Calvin Clark, her son-in-law.

Mary Ann was buried next to her husband, who died on 25 April, 1898, at Immanuel Union (Manship) Church in Cheswold.