1. To find supporting documents of who Isiah Pease born abt 1818 in Lexington Plantation of Maine, parents are. Our Bible that burned in a house fire, listed Elijah Pease and Mary "Polly" Collins as his parents. Elijah and Mary had 13 children. Mary is listed as the guardian of the minor children in probate records. Children not listed. Elijah died in 1823, a few days after falling into a fire at Gilmond Pond, Lexington Plantation, Maine. Mary/Polly died in 1833. I found several probate news articles for Isaiah's death in 1867, listing his wife and children, not his parents. He is not Isaiah D Pease. I did a timeline. Isaiah is listed in his "brother's" household in 1850 Lexington, Somerset, Maine Census. He is in his brother-in-law's household in 1860 Augusta, Kennebec, Maine Census.
2. To find out who Marietta Downs's father is. She married Isaiah's son George A Pease. She is the daughter of Melvina Downs and an unknown father. She was most likely born in 1866 in Belgrade, Kennebec, Maine. She died in 1955 in Knox, Rockland, Maine. My mother is listed in her home on the 1940 Belgrade Maine Census.
I hope this helps if someone decide to research them.