1789 At the November term of the Burlington County Orphans Court, Isaac Ivins petitioned to be appointed guardian of his minor children under the age of fourteen: Barzillai, Thomas, Elizabeth, Mary, Margaret, and Ann Ivins. He was appointed guardian until they achieved age 14 upon posting of bond. 
1791 The account of the estate of Isaac Ivins [married to Mary Hopkins] named his 32 living children and grand-children, including son, Isaac Ivins, and his grand-children: Barzillai, Thomas, Elizabeth, Mary, Margaret, and Ann as children of Isaac. [Photocopy, Estate account of Isaac Ivins naming children and grand-children.] 
1801 Barzillai Ivins and Nancy Decou were married on January 20 in Burlington County, New Jersey. 
1818 Letters of administration for the estate of Ann Ivins, formerly Ann De Cou, of Burlington County, were issued to her husband Barzillai Ivins. Dated August 29. 
1801 Ann Decou and Barzillai Ivins were married. 
1810 Grandson, Thomas Ivins (son of Barzillai Ivins) recieved $800 in the will of John Decou of Mansfield Twp, Burlington County, to be at interest until said grandson is 21 and in case of his death before 21, said sum to said daughter Ann. This suggests that John Decou's daughter Ann married Barzillai Ivins. Barzillai and Daniel Ivins had roles in the wills of John Decou and his son William. I have no evidence that this is the same as Barzillai, son of Isaac and Hannah Ivins, other than a plausible age for marriage.
1816 Barzilla Ivins and Rebecca Stokes got a marriage license in New Jersey. Dated October 24. 
 New Jersey Probate Records, 1678-1980, Burlington, Orphans Court Minutes 1-66, [FamilySearchImage].
 Burlington County, New Jersey, Miscellaneous Probate Papers 1778-1815, book I, image 94, [FamilySearchImage].
 Burlington County, New Jersey, Marriages, 1795-1865, [FamilySearchImage], [FamilySearchRecord], [FHLCatalog].
 New Jersey Probate Records, 1678-1980, Burlington, Administration and Guardian Record A-176, [FamilySearchImage].
 S. Ella DeCou and John Allen DeCou, The genealogy of the DeCou family (1910), 147, Chart G, [HathiTrust].
 New Jersey, County Marriages, 1682-1956, [FamilySearchImage], [FamilySearchRecord].