I am making an assumption that the "Levi, of Ezekiel" in the marriage entry belongs in this family group, because the dates fit. Also, the names of their children reflect the names of the previous generation.
His grave is in Providence Historical Cemetery #1, North Burial Ground. His gravestone has been photographed. Also engraved on this stone are his wife and son, and Louisa P. Remington -- probably his cousin, daughter of his mother's brother John. I have made an assumption that Ambrose's middle initial "N" stands for Nichols, because his paternal grandmother was Sarah Nichols. His grandmother Sarah (Nichols) Whitford had a brother Ambrose Nichols who mentioned, by name, Ambrose N. Whitford in his will of 1874.
The 1860 Census shows Ambrose N. Whitford, age 39, living in Kent County with Matilda Whitford, age 41, and George N. Whitford, age 7. For some reason, Albert D. Remington is also living in the household (along with a couple of other individuals). He may be the same Albert D. Remington who married Carrie Knight c.1861 (although the ages are different). This Albert is the brother of Louisa P. Remington, whose name is on the gravestone referred to above, and would likewise be a first cousin to Ambrose.