Jennie was born in Reading, Berks County, PA. She was the daughter of William Morris and Lydiann M (Rissmiller) Gift. She had one biological brother, William Henry, and was raised with 5 step siblings, Maggie and Mary Rauenzahn (from Lydia's first marriage), Catharine, Charles, and Robert Gift (from William's first marriage). Her father died in 1898 of lung affection 2 weeks after William Henry is born. On July 27, 1911, she married Elias Heiser in the District Attorney's office at the Reading courthouse. Because she was only 18 years old at the time, her mother's consent was necessary. The wedding announcement is noted in the Reading Eagle.
Elias and Jennie had 10 children. Their first son, Harry E, suffered from spinal meningitis and died of bronchopneumonia shortly before his first birthday. They resided mostly in the Reading area. The 1920 Census shows them living at 630 North 8th Street. In 1930, they resided at 544 Poplar Lane, just around the corner from their previous residence. The 1940 Census shows them living in Bethel with children Raymond, Hilda, June, Jack, and Frances. The 1942 Reading City Directory lists their address as 552 Fern Ave. in Reading, a row home built in the 1840s. In August 1937, the Heiser Family got together at Mineral Spring Park.
The Funeral Records of St. John's German Lutheran Church in Reading lists Jennie's date of birth as 07 Sep 1892. Her death certificate lists her date of birth as 10 Sep 1892.
At the end of her life, Jennie lived with George and Hilda (Heiser) Rissmiller in West Reading. She died of coronary artery disease (cardiac decompensation) and is buried with her husband at Forest Hills Memorial Park (Block E near circle) in Reiffton, PA. Several children and their spouses are buried nearby.