She had three brothers: Lawrence, Joseph Elbert and James Jr.[1] Haddon attended business college and worked as an advertising agent before running a welcoming service.

[2][4][7] During her time in the legislature, she advocated for children with disabilities, including establishing the Lakeland Village in Spokane and Olympic Peninsula Enterprises.

[8] With her second election, Haddon became the first woman to have held the same seats in both chambers of the Washington state legislature as her mother.

[2] In 1963, she introduced legislation alongside John Stender to prevent psychological testing of students without parental consent.

[13] The Frances Haddon Morgan Center was established in Bremerton in 1972, to house children with autism and later adults with disabilities, although it was abandoned in the 2010s and was torn down in 2022.