From the History and Genealogy of the Bieber, Beaver, Biever, Beeber Family, by the Reverend Irvin M. Beaver (Reading, Pennsylvania; 1939), page 527-528:

In 1785 he is named in Shenandoah Co., Va., Census as married and one child. Michael Beaver, Sr., was m. twice: first, before 1785, to Susan Mauck, b. ----, d. before 1799. Issue 4 children, viz., Michael, Jr., Joseph, Eliza, Susan. He m. 2nd, June 7, 1799 (accord. to Shenandoah Co., marriage record, p. 56, "Michael Beaver and Molly Mauck, June 7, 1799---James Huffman.") to Mary (Molly) Mauck, a twin sister of his first wife. Mary or Molly was b. 1773, d. 1827, aged 54 years. She is bur. on the old Beaver homestead by the side of her son, Michael Beaver, Jr., on Pennyroyal Hill. Her stone reads: "Mary Beaver, born 1773, died 1827, aged 54 years." Issue 4 children, viz., Ellias, Nancy or Susanna, Levi, Lewis.

Michael Beaver, Sr., moved from Pass Run, Page Co., Va., to Ross Co., O., in 1796, and after two years he went to Kentucky, but returned to Ross Co., O., near Chillicothe, in 1800, where he settled after buying a large farm of eleven hundred acres of land in the Chilton Survey on Deer Creek, Ohio, where he lived and reared his family, died there and buried in the private graveyard on the old homestead. No stone has been found marking his grave. His first wife died in Virginia; no stone has been found marking her grave. He served in the War of 1812 under Col. Clark, whose regiment was mustered out in 1813 on the farm of Michael Beaver. Michael and Susan Mauck Beaver: issue 4 children. Michael and Mary (Molly) Mauck Beaver: issue 4 children.