Mamie Johnson had one sister, Lillie Belle Barber.
Mamie was the Abbott family's trusted housekeeper for many years. She was an invaluable treasure to patriarch, John Abbott, Sr., and functioned as a surrogate mother to John's three oldest children: Jack, Ashley and Traci. John and his first wife Dina Mergeron divorced after she left John and the children, prior to their arrival in Genoa City. When Jack was eighteen, Dina sent him a letter asking him to join her in Paris.
However, Mamie recognized Dina's handwriting and intercepted the letter ensuring that Jack would not leave John and the rest of the family. Mamie often proved to be a thorn in the side of John's younger second wife, Jill Abbott. Often, Jill and Mamie found themselves at odds with each other as Mamie would easily find out Jill's latest schemes which would incense Jill as she wished that Mamie would act less like a confidante and more like the hired help.
In 1980, Mamie's two nieces came to town: physician Olivia Barber and aspiring ballerina turned runaway Drucilla Barber. Liv was always very close to her Aunt Mamie. Dru ran away from home as a teenager due to her problematic relationship with her mother, Lillie Belle. She went to stay with her Aunt Mamie. The sisters would eventually marry half-brothers Malcolm Winters and Neil Winters, respectively.
In 1995, after John filed for a divorce from Jill (during their second marriage), he suffered a stroke. Nursing him back to health, Mamie confessed to John that she was in love with him. John admitted his love for Mamie, but soon lapsed into a coma. When Jill learned of their relationship, she fired Mamie and offered her millions of dollars to leave Genoa City. When John recovered from his coma, he agreed to remain with Jill for the sake of his youngest child, Billy Abbott. A devastated Mamie accepted Jill's money and left town with Chancellor Industries executive Trent Jordan.
However, Mamie remained close to John and the Abbott family. She returned to Genoa City several times, visiting both the Abbotts and her own family.
In 1996, both Dina Mergeron and Mamie sent flowers to remember John as they neither was able to attend his funeral.
In 1999, Mamie returned. Colleen Carlton had become sullen and repentant, skipping dance classes to spend her time with new friends of questionable character. They introduced her to marijuana and it was just a matter of time before her mother found out. Initial measures of yelling and threats were not enough. She was caught smoking marijuana in school and expelled. Her attitude was continually harsh and rude. Traci, Steve Connolly and Brad Carlton all agreed - the only solution was boarding school.
But Colleen's grandfather, John, stated his confidence in her. John offered to let her move to Genoa City and live with him. They finally gave in and let Colleen have one last chance by living under the supervision of John and the former maid who had raised Traci, Mamie.
In 2004, Mamie left to travel the world.
In 2010, Mamie and Dina both sent flowers for Colleen's funeral.
- Lillie Belle Barber (sister)