From the History and Genealogy of the Bieber, Beaver, Biever, Beeber Family, by the Reverend Irvin M. Beaver (Reading, Pennsylvania; 1939), page 615:

IV. 1. Anna Mauck, b. July 18, 1790, d. Dec. 15, 1865, m. first, Oct. 10, 1810, to John Koontz, b. ----, d. 1817. Issue 5 children. (See gen.) Anna Mauck Koontz and her children went to Hancock Co., Ill., where she m. second Thomas Burnett.

From the History of The Descendents of John Koontz, by Lowell L. Koontz (Alexandria, Virginia: 1979), pp. 28-29.

Anna Mauck was the first child of Abraham Mauck and Mary Beaver who was the eighth child of Conrad Beaver. Anna was b. 18 July 1790 and d. 15 Dec. 1865 m. 10 Oct. 1810 to John Koontz. Anna became a member of the Mill Creek Church after 1831.

Anna m/2 Thomas Burnett of Hancock Co., Ill. The parents of Anna Mauck, Abraham Mauck and Mary Beaver were m. 29 Oct. 1789 by Elder John Koontz. The father of Abraham Mauck, Anna's grandfather, was Daniel Mauck who m. Barbara Harnsberger and was living at Woodstock, Va. at the time of Abraham's marriage.