From NPR authored by Nina Totenberg:
When 19-year-old Sandra Day entered Stanford Law School in 1949, her frequent seatmate was 26-year-old Bill Rehnquist, attending Stanford on the GI Bill. The two shared their equally meticulous class notes and eventually were dating regularly. But by December of their second year, she broke up with him while somehow retaining what she called their “study buddy” relationship; she even entered the moot-court competition with Rehnquist, and the pair finished second.
When Rehnquist graduated a semester early and went off to Washington, D.C., for a Supreme Court clerkship, Sandra wrote to her parents that school “does not seem the same” without him. “We all truly hated to see him leave, in spite of, perhaps, even because of, all the funny things he does. He certainly has a brilliant career ahead,” she added.
By then, Sandra was dating John O’Connor, whom she met over a proofreading assignment on the prestigious Stanford Law Review. After their first meeting, John suggested they finish their proofreading over a beer, and the two soon were inseparable. John was charming and funny, and unlike a couple of beaus who had jilted her, he was not cowed by her smarts.
But in March, just about the time that Day and O’Connor were going out on their 40th date in 40 days, Sandra got a letter from Rehnquist telling her he wanted to see her to talk about “important things.” And in a March 29 letter, he popped the question. ‘To be specific, Sandy, will you marry me this summer?'”