Stevenson was born in Palo Alto, California, and moved to Lewiston, Idaho, with her family at the age of 13 when her father accepted a job with PotlatchDeltic.

[1][2] Stevenson earned a Bachelor of Arts degree English and another in Spanish from Boston University.

[2] She died of heart problems while in office and Republican Governor Brad Little appointed Aaron von Ehlinger to the remainder of her term.

[8] [9] [6] In 1978, Stevenson married Walter Noel Greenham (1941–2015), a Navy veteran and computer engineer.

[2][14] Stevenson died on May 11, 2020, at age 75, from complications of a heart attack she suffered a week prior.