Mahala Mottice was evidently a daughter of Peter and Pheby Mottice. I have found no birth or death records for her, but I infer that she was born around 1805 and died between 1828 and 1836.
The first mention of Mahala is in the historical records of the Presbyterian Church in Waynesburg:
"On the fourth Sabbath of May 25, 1823 the Lord's Supper was administered . . . accepted were Nancy Mottice and Mahala Mottice."
There is no other identification of who these women (or girls) were. I could not find any further records of Mahala in the Church archives. Other historical records from ancestry.com and family trees from rootsweb.com indicate that a Mahala Mottice (or Motties) married Thomas Davis in Stark Co. on May 11, 1828 (Marriage Index: Selected Counties of Ohio 1789-1850).
Significantly, several of these histories show Mahala and Thomas with a daughter, Elizabeth, who marries an unnamed Firestone. Charles Mottice's history identifies a grand-daughter of Peter named Elizabeth Firestone who also figures prominently in Peter's will.
In the meantime, Thomas Davis is recorded as having re-married in 1836. I must therefore speculate that Mahala died sometime between 1828 and 1836, and that she bore Elizabeth during this time period as well.