Elizabeth E. Mullett gives the following dates for Barbara Nicely:
birth--January 26, 1816
death--February 28, 191257

Barbara is found in an Orphan’s Court petition in Greene Co., PA in 1833, which identifies Jacob as her father.112

Ted McClelland identifies Barbara as a daughter of Jacob Knisley and Elizabeth McClelland.117

1870 Middlebourne Post Office, Centerville Twp., Tyler Co., WV, p. 23
Grim, Barbara, 54, keeping house, Real Estate value $2000, Personal Estate value $300, b. PA
Mary, 13, b. VA
Jesse, b. VA

1880 Census, Tyler Co., WV
Grim, Barbara, 65, keeping house, b. PA, parents b. PA
Cooper, Jessee, 18, grandson, farmer, b. WV, parents b. PA

In 1900 Barbara is listed in the census with her son Jessie. She identified herself as a widow, 84, b. Jan. 1816 and her parents b. in PA.

Tyler Co. Register of Deaths, Book 1, 1853-1903, p. 92, line 3 (1902)
Name: Grim, Barbara
Date of Death: Feb. 28
Residence: Bearsville
Cause of Death: Pneumonia Fever
Age: 86
Parents: none given
Date of Birth: 1816
Occupation: Housekeeper
Marital Status: Married
Reported by: John L. Grim, son

Tyler County Register of Deaths, Book 2, 1901-1906, p. 38, line 167:
Name: Barbara N. Grim
Age: 86y 0m 16d
Date of Death: Feb. 9, 1902
Marital status: widow
Place of Birth: Greene Co., PA
Place of Death: Sancho, Tyler Co., WV
Cause of Death: Pneumonia

Note difference in dates; one is Feb. 28, 1902, the other is Feb. 9, 1902.