The nation is mourning the passing of former first lady Barbara Bush, wife of President George H.W.

Bush passed away shortly after deciding to forgo further medical treatments for her failing health, a family spokesman said. She was 92 years old.

[PHOTOS: Barbara Bush through the years]

Having been hospitalized numerous times while battling congestive heart failure and chronic obstructive pulmonary disease, she decided Sunday that she wanted to be "surrounded by a family she adores," according to a statement released by the office of former President George H.W. Bush.

Bush's funeral will be held at St. Martin's Episcopal Church in Houston, Texas at 11 a.m. on Saturday, April 21. The service is closed to the public. Mr. and Mrs. Bush have been devoted members of the church since the 1950s.

Mrs. Bush will lay in repose between noon and midnight on Friday, April 20 at St. Martin's Church.

Members of the public wishing to pay their respects to Mrs. Bush may do so at that time, but must take a shuttle to St. Martin's from Second Baptist Church, where they will be subject to security.

Barbara Bush was born in New York City on June 8, 1925. In 1945, she married George H.W. Bush, who became vice president in 1981 and president in 1989.

The two were married two years after Barbara Bush attended Smith College. She was just 19 when they married.

In the same year, she started the Barbara Bush Foundation for Family Literacy.

[READ: Things to know about Barbara Bush]

Driven by her passion for reading, she set out to raise awareness about the importance of family literacy, giving children and their parents the opportunity to learn and achieve together.

Barbara Bush stated that if more people could read or write, “we could be much closer to solving so many other problems that our country faces.”

The foundation focuses on fulfilling its mission by providing low-income families across the nation with scholarships to learn together.

Barbara Bush was a relative of Franklin Pierce, the 14th president of the United States. The two were fourth cousins four times removed.

Barbara Bush was diagnosed with Graves' disease in 1989 after she lost 18 pounds in three months.
Graves' disease causes mood and body changes when the immune system "mistakenly attacks" the thyroid gland, causing overproduction of the hormone thyroxine, according to the Mayo Clinic.
She later began taking medication, including steroids, to treat the condition and received radiation therapy in 1990 for her eyes as part of the treatment.

On Tuesday night, President Jimmy Carter and former first lady Rosalynn Carter released a joint statement saying:

"Rosalynn and I are saddened by the death of Barbara Bush. She touched the hearts of millions with her warmth, generosity, and keen wit.  The matriarch of a family dedicated to serving, she urged volunteerism as a way for all citizens to participate in our nation’s progress. Through her own work to promote literacy as a value in every American home, countless families now have the knowledge and skills they need to thrive in all aspects of their lives. She will be missed." 

Mrs. Bush brought a grandmotherly style to buttoned-down Washington, often appearing in her trademark fake pearl chokers and displaying no vanity about her white hair and wrinkles.

“What you see with me is what you get. I’m not running for president — George Bush is,” she said at the 1988 Republican National Convention, where her husband, then vice president, was nominated to succeed Ronald Reagan.

The Bushes, who were married Jan. 6, 1945, had the longest marriage of any presidential couple in American history. And Mrs. Bush was one of only two first ladies who had a child who was elected president. The other was Abigail Adams, wife of John Adams and mother of John Quincy Adams.

“I had the best job in America,” she wrote in a 1994 memoir describing her time in the White House. “Every single day was interesting, rewarding, and sometimes just plain fun.”

Bush's public image was that of a self-sacrificing, supportive spouse who referred to her husband as her “hero.”

In the White House, “you need a friend, someone who loves you, who’s going to say, ‘You are great,’” Mrs. Bush said in a 1992 television interview.

Stay with WSBTV.com and Channel 2 Action News as this story develops.  

In all, the Bushes made more than two dozen moves that circled half the globe before landing at the White House in 1989. Opinion polls taken over the next four years often showed her approval ratings higher than her husband’s.

The couple’s final move, after Bush lost the 1992 election to Bill Clinton, was to Houston, where they built what she termed their “dream house” in an affluent neighborhood. The Bush family also had an oceanfront summer home in Kennebunkport, Maine.

After retiring to Houston, the Bushes helped raise funds for charities and appeared frequently at events such as Houston Astros baseball games. Public schools in the Houston area are named for both of them.

In 1990, Barbara Bush gave the commencement address at all-women Wellesley College. Some had protested her selection because she was prominent only through the achievements of her husband. Her speech that day was rated by a survey of scholars in 1999 as one of the top 100 speeches of the century.

“Cherish your human connections,” Mrs. Bush told graduates. “At the end of your life, you will never regret not having passed one more test, winning one more verdict or not closing one more deal. You will regret time not spent with a husband, a child, a friend or a parent.”

Funeral arrangements were released for Mrs. Bush late Tuesday evening.

She will lie in repose between noon and midnight on Friday, April 20 at St. Martin's Church in Houston, Texas.

Bush's funeral will be invitation only on Saturday April 21 also at St. Martin's Church. Guests will need to go through security at Second Baptist Church in Houston and then take a shuttle to St. Martin's.

The Associated Press contribute to this article.