Bertha A. (Cain) Joiner was born July 14, 1917. Her family moved to Sycamore when she was nine years old. She attended Sycamore High School and graduated in 1935. On August 24 of that same year, she married her childhood sweetheart, Ralph Joiner. They were married for 73 years.  

Bertha was known as an excellent cook, a wonderful homemaker and mother, and well-known for making brownies and little pizzas during her life. She was a member of the First Baptist Church of Sycamore and was involved in women's ministries, Sunday School, and serving others from her work in the kitchen. 

Bertha did taxes for her husband in her professional career, later becoming his office assistant in the county clerk's office.

During his tenure at the courthouse, Bertha and Ralph realized that their office's myriad of records and documents had extreme value to the community. During their service between 1956 and 1976, they would mark "save" on the boxes containing the records. Ralph dreamed that the old records and other memorabilia scattered throughout the courthouse could find a new, permanent home. In 1989, the first official public archives for DeKalb County opened. The location was named the Joiner History Room in dedication to Bertha and Ralph to recognize their efforts in preserving the County's historical documents. In 1998, the Joiner History Room had outgrown its space and agreed to utilize an area in the Sycamore Public Library. The County archives moved once again in 2019; it became a permanent part of the new DeKalb County History Center and their newly renovated facility located in Sycamore.

In 2008, the Joiner History Room Endowment Fund was started at the DeKalb County Community Foundation with a contribution from Patsy and Bill Lundberg to honor their mother, Phyllis, the first DeKalb County Historian for the Joiner History Room. It was also in 2008 that Ralph M. Joiner passed away. The Fund accepted memorial gifts from other donors who wanted to honor Ralph's memory and show appreciation for the History Room's services to DeKalb County. 

Bertha A. (Cain) Joiner passed away on Monday, April 18, 2011. The Joiner History Room Endowment Fund received a number of contributions in her memory following her passing. The legacy of Bertha and Ralph Joiner lives on through the workings of the Joiner History Room and the Joiner History Room Endowment Fund.