George Bush said marrying Barbara, whom he called "Bar," was "the thing I did right." But the marriage nearly did not take place. While they were engaged, his bomber was shot down by the Japanese in the Pacific in 1944. He bailed out and was rescued in the ocean by a submarine crew, but his crewmates died.

"When you're 18, you think everybody is invincible. ... I mean, that was stupid - but I knew he was going to come home. He was Superman," she told CNN in 2003.

After leaving the White House, she found time to write her memoirs. In 1990, she authored "Millie's Book," a humorous look at the adventures of the family's English springer spaniel in the White House.

In one of their last public appearances, the Bushes attended the 2017 Super Bowl in Houston with George performing the ceremonial pregame coin flip. Only a few days before, the couple had been released from a hospital where George had been treated for pneumonia and Barbara for bronchitis.

Reuters