Hi Beverly,
I found this family group in the 1880 Census of Rhode Island (living in Lincoln, RI, next town up from North Providence wherein can be found Greystone village). I live in the neighboring village to Greystone, and wondered if this might be the family you're seeking. Lincoln is next door to Central Falls, RI.
Family Number 171
REDMAN, John, 42y, head of family, born England (works in Sayles Bleachery)
REDMAN, Hannah, 40y, wife, born England
REDMAN Edgar, 19y, son, born New Jersey (sic)
REDMAN, Ada, 14y, daughter, born New York (sic)
REDMAN, John Jr., 9y, son, born New York (sic)
REDMAN, Frank, 7y, son, born New York (sic)
and also:
Edgar REDMAN, 27y, son of John & Hannah (France) Redman
Mary A. THORNLEY, 22y, daughter of Squire & Jane (Tuthell) Thornley
m Lincoln, RI 25 Dec 1886
Frank REDMAN, died Central Falls, RI 28 Apr 1923; 45y, 9 mos, 29d; son of John & Hannah (France) Redman; born New York, NY June 29 (No Year); place of death 78 Rand St, Central Falls, RI; single; occupation: chemist making blue dye; burial Moshassuck Cemetery, Central Falls, RI; cause of death: suicide by asphyxia from illuminating gas.
If you can access Family Search, here's the link to his death record:
https://www.familysearch.org/ark:/61903/3:1:3QSQ-G9H7-ZHPQ?i=592John REDMAN, son of John & Hannah (France) Redman; d Cranston, RI 29 May 1935 (64y) [State Hospital of Acute Lobar Pneumonia]; born 1870; single; 64y; occupation: janitor; burial Moshassuck Cemetery, Central Falls, RI
Hannah Maria (France) REDMAN, daughter of Thomas and Sarah France, died 78 Rand Street, Central Falls, RI 29 Oct 1924 (84y); born England November (No Year Listed); widow of "Frank" Redman; buried Moshassuck Cemetery, Central Falls, RI; cause of death: broncho-pneumonia, chronic myocarditis and senility; informant: daughter, Mrs. Edwin Bamford (this would be Ada Redman)
https://www.familysearch.org/ark:/61903/3:1:3QSQ-G9H7-CWZV?i=609Ada (Redman) BAMFORD, daughter of John & Hannah (France) Redman; died 112 Rand St. Central Falls, RI 21 Dec 1930 (65y, 7 mos, 14d); born New York City, NY 6 May 1865; wife of Edwin Bamford; buried Moshassuck Cemetery, Central Falls; cause of death cerebral hemorrhage.
https://www.familysearch.org/ark:/61903/3:1:3QS7-99H7-DDN8?i=770 and
https://www.findagrave.com/memorial/search?firstname=&middlename=&lastname=redman&birthyear=&birthyearfilter=&deathyear=&deathyearfilter=&location=Central+Falls%2C+Providence+County%2C+Rhode+Island%2C+United+States+of+America&locationId=city_125812&memorialid=&datefilter=&orderby=&page=1#sr-96536688https://www.findagrave.com/memorial/107608853/john-redmanhttps://www.findagrave.com/memorial/107608851/hannah-maria-redmanhttps://www.findagrave.com/memorial/107608849/edgar-redmanhttps://www.findagrave.com/memorial/107608850/frank-redmanhttps://www.findagrave.com/memorial/103956308/ada-r-bamfordYou mentioned Frank was your ancestor, yet he died single This doesn't seem to be the correct family but they were only Redmans I could find in Central Falls, RI fitting the description you gave in your primary post. I don't know how Sanford, Maine comes into play, but perhaps they came through New Brunswick to the USA? The family did live in New Jersey and New York (where their children were born) before coming to Rhode Island. Hope some of this helps.