You just can't do some love stories justice.

Back in the 1950s, William Rehnquist, the future Supreme Court chief justice, proposed to his law school classmate, Sandra Day – later to be O'Connor and a future associate justice on the high court, a forthcoming book reveals.

Biographer Evan Thomas, whose book "First" is set to be released March 2019, discovered the decades-old secret in O'Connor's old letters, NPR reported.

In a letter, Rehnquist wrote to O'Connor to discuss "important things."

"To be specific, Sandy, will you marry me this summer?" Rehnquist wrote.

O'Connor and Rehnquist met in 1949 at Stanford Law School, where O'Connor was the only woman in her class. The two soon began dating casually, but broke up in December of their second year.

At the time of Rehnquist's proposal, O'Connor was already dating her future husband, John, per NPR. They married in 1952. A year later, Rehnquist married his wife, Nan.

O'Connor's son, Jay O'Connor, told NPR that he and his siblings were aware of their mother's former relationship with Rehnquist, but noted that "dating was pretty innocent in the '50s."

Sandra Day O'Connor and Rehnquist remained close friends throughout their lives, staying in touch when Rehnquist was appointed to the Supreme Court in 1972. The two served on the bench together from O'Connor's 1981 appointment as the first woman on the Supreme Court to Rehnquist's death in 2005. O'Connor retired a year later.

Jay O'Connor called it an "amazing accident of history" that his mother and her law school friend both ended up on the high court.

"Not only did they have a wonderful working relationship for over 25 years on the court they had a wonderful friendship their entire life," he told NPR.

Sandra Day O'Connor, 88, recently announced her retirement from public life and her diagnosis of what doctors believe is the early stages of Alzheimer's disease. In an open letter, she discussed her diagnosis.

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