Regret to report I have nothing to contribute re your brick wall for David or Daniel Green
Of the children, the Stephen Purinton/Susan Green union produced the most information. You may already have all this. If so, I figure no harm done. Good luck in your search. There is supposed to be a family history center in Litchfield. Might be worth writing there if you have not already done so.
Rev. Stephen Purinton, born 22 January 1798, son of Rev. Humphrey Purinton and Thankful Snow, married in 1835 Susan Green, daughter of Daniel Green and Mary Blaisdell. Rev. Stephen, the pastor of the Free Will Baptist Church on the Plains Road in Litchfield, Maine, died 26 December 1879 and is buried in LItchfield. His daughter, Louise E. Purinton, born 14 September 1842 (died November 1908) married on 15 September 1861 Edward Shorey (son of Hiram Shorey and Rebecca Chadbourne of Berwick) and had a son Hiram Elmer Shorey, born 9 August 1862, died Chicago, 29 March 1944, buried Plains Cemetery, Litchfield.
Hiram Elmer Shorey, in 1905, was one of the four founders of the Rotary Club of Chicago, which grew into the worldwide service organization Rotary International.
Name: Holman G Purinton
Death Date: 09 Feb 1928
Death Place: Chicago, Cook, Illinois
Birth Date: 22 Apr 1847
Birthplace: Cowdrein, Maine
Father: Stephen Purinton
Father's Birth Place: Maine
Mother: Susan Green
Mother's Birth Place: Maine
Spouse: Mary Purinton
Burial Date: 11 Feb 1928
Cemetery: Rose Hill
Digital Folder Number: 4205902
Image Number: 1786
Film Number: 1878042
Volume/Page/Certificate Number: rn 4089
Holman G Purinton married Helen Morrison Worthington (1873-1902) on 24 June 1899 in Jacksonville, Illinois, daughter of George Balfour Worthington and Hannah Morrison Criswell.
Holman served in both the Spanish American and Phillippine American Wars.
The New York Times. August 17, 1899
Chicago, August 16 - Major Holman G. Purinton, of 4217 Calumet Avenue, who served during the war with the Second Regiment, has been made a Captain of the Twenty-ninth Volunteer Infantry. He received his official notice of appointment today from W. H. Carter, Assistant Adjutant General at Washington, and at once wired his acceptance. The Twenty-ninth is now stationed at Fort McPherson, Ga., and will remain there a month. Then it will be sent to San Francisco, en route to the Phillippines. Capt. Purinton will join the regiment in ten days.
He had some reverses as a businessman.
1910 Census, Cook Co., IL, Chicago, 3rd Ward, East 36th Pl
Mary M Minckler, head, 50, widow, salewoman, dry goods
Henrietta Naylor, lodger,59, widow, saleswoman, publishers
Holman G Purinton, lodger,62,widower, b. Maine, merchant
Wonder if the G in Holman G. Purinton stands for Green