This Peter ‘the miller’ Brown 's profile and that of Peter ‘the miller’ Brown show death on 9 March 1692.
Did both provably die on the same date? Might they be same person? Hmm...
Staying away from Cutter who gives neither a source nor a helpful, convincing rationale, here are two other public domain books whose authors chose to connect both Peters Brown as father and son:—
AUTHOR: Royal Ralph Hinman wondered out loud by beginning with the word "If". He wrote:
"If Peter Brown, of Wi., was a son of Peter, who came to Salem in teh Mayflower, he must have been a sall child, and his name not mentioned, as none of his younger children were mentioned by name in the settlement of his estate. ("Facts from W. R. Russell, Reg. Deeds, and Old Col. Rec.) Peter, of Salem, d. 1633; peter, of Wi., was b. 1632; his monument at Wi., says he d. 1692, aged 60. The record of deeds at Wi.,, notes him as the owner of tracts of land at Wi., from 1658 to 1664. Peter, of Wi., m Mary Gillet, of Wi., July 15, 1658, and died 1692; had children, Mary, b. May 2, 1659; Hanna, b. Sept. 29, 1660; Abigail, b. Aug. 8, 1662; Hepzibah, b. Nov. 19, 1664; Peter, Jr., b. March 12, 1664; John, b. Jan. 8, 1668; Jonathan, b. March 30, 1670; Cornelius, b. July 30, 1672; Hester, b. May 22, 1673; Esabell, b. June 9, 1676; Debora, b. Feb. 12, 1678; Sara, b. Augu. 20, 1681. (Wi. Rec.) He had two other daughters who were married. Estate, £408."
SOURCE: Royal Ralph Hinman. 1852. A Catalogue of the Names of the Early Puritan Settlers of the Colony of Connecticut with the Time of Their Arrival in the Country and Colony, Their Standing in Society, Place of Residence, Condition in Life, Where From, Business, &c., as Far as Is Found on Record. Vol. 1. Hartford, Connecticut, USA: Case, Tiffany & Company. https://www.google.com/books/edition/A_Catalogue_of_the_Names_of_th....
AUTHOR: Annie Haxtun wrote:—
"PETER, THE SON.
“The early demise of the father left the continuance of the history with the children and for our purpose, so much hinging on his after residence, Peter will answer for “he, with Gov. Bradford and thirty others were among the first purchasers of Dartmouth in 1652,” making him, as he was born in 1632, only twenty years of age when admitted to this enterprise of the “solid men.”
“Some affinity to Connecticut, perhaps a drawing to Jonathan Brewster (James Rogers), and other wanderers from the fold of Plymouth’s claims, took him to Windsor, Conn.
“He went from Duxbury there, and the benefit of his Dartmouth venture may have told for him as an investment.“
PETER, JR.
“Dr. Stiles, in his history of ancient Windsor, simply announces Peter Brown, of the Mayflower, giving the usual records, then puts as “Family 2, Peter (son of above), born 1632; removed from Duxbury, Mass.; married, July 15, 16388, Mary (probably daughter of Jonathan or Nathan) Gillet; he admitted to Windsor Church June 22, 1662 (O. C. R.); bo’t in Windsor, same year (June 28), house and lot of Robert Hayward, ‘near the mill,” and doubtless resided there until he ‘bought the Josias Dllsworth place, near William Phelps, Jr., January 31, 1664, which since has been called the Peter Brown place, and became conspicuous about the beginning of the present century, because of the opposition of its then occupant (a Peter Brown) to the opening of a new road, which left his house in the lot, etc.
“This house was demolished some thirty years since. He contributed 9s 7d. to the Connecticut Colonial relief fund for the poor of other colonies, 1676; his wife owned Half Way Covenant, in Windsor Church, July 17, 1659, O.C.R. Peter Brown died March 9, 1692, aged 60, estate £408 14s. 6d.”
“This Peter Brown was a miller, and, January 1658-9, at town meeting, it was voted “that Peter Brown that keeps the mill, should take but single toll, or the sixteenth part of all grain for his grinding, only of Indian corn it was voted by the major part that he should take toll and hal, from this time until 25th of March next ensuing, but no longer.”
“The Indian corn being more difficult to grind, larger rated were required as compensation.”
SOURCE: Haxtun, Annie Arnoux. (1897-1899) 1968. “Peter Brown, Thirty-Third Signer.” In Signers of the Mayflower Compact. Baltimore, Maryland, USA: Genealogical Publishing Company. https://www.google.com/books/edition/Signers_of_the_Mayflower_Compa....
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I can't find anything else in Public Domain of value. Maybe someone convincingly elucidated on the subject giving sources or some convincing rationale(s), it'd be an author's work found at AmericanAncestors or in a NEGHS book published after 1964.