HOUSTON – Barbara Bush, the wife of former President George H.W. Bush and mother of former President George W. Bush, is in failing health and will not seek additional medical treatment, the Bush family spokesman announced Sunday.

"Following a recent series of hospitalizations, and after consulting her family and doctors, Mrs. Bush, now age 92, has decided not to seek additional medical treatment and will instead focus on comfort care," the spokesman said in a written statement.

"It will not surprise those who know her that Barbara Bush has been a rock in the face of her failing health, worrying not for herself — thanks to her abiding faith — but for others," the spokesman said in the statement.

The entire statement from the family's spokesman follows:

"Following a recent series of hospitalizations, and after consulting her family and doctors, Mrs. Bush, now age 92, has decided not to seek additional medical treatment and will instead focus on comfort care. It will not surprise those who know her that Barbara Bush has been a rock in the face of her failing health, worrying not for herself — thanks to her abiding faith — but for others. She is surrounded by a family she adores, and appreciates the many kind messages and especially the prayers she is receiving."

VIDEO: Former first lady Barbara Bush in failing health

The Bushes have been married for 73 years.

Bush, who is at home in Houston, is one of only two first ladies who was also the mother of a president. The other was Abigail Adams, wife of John Adams, the nation's second president, and mother of John Quincy Adams, the sixth president.

Bush married George H.W. Bush on Jan. 6, 1945. They had six children and have been married longer than any presidential couple in American history.

VIDEO: Inside the legacy of Bush's 73-year marriage

Eight years after she and her husband left the White House, Mrs. Bush stood with her husband as their son George W. was sworn in as the 43rd president.

President Donald Trump's press secretary, Sarah Huckabee Sanders, said in a statement Sunday evening that "the President's and first lady's prayers are with all of the Bush family during this time."

Bush is known for her white hair and her triple-strand fake pearl necklace.

Her brown hair began to gray in the 1950s, while her 3-year-old daughter Pauline, known to her family as Robin, underwent treatment for leukemia and eventually died in October 1953. She later said dyed hair didn't look good on her and credited the color to the public's perception of her as "everybody's grandmother."

Her pearls sparked a national fashion trend when she wore them to her husband's inauguration in 1989. The pearls became synonymous with Bush, who later said she selected them to hide the wrinkles in her neck. The candid admission only bolstered her common sense and down-to-earth public image.

Her 93-year-old husband, the nation's 41st president who served from 1989 to 1993, also has had health issues in recent years. In April 2017, he was hospitalized in Houston for two weeks for a mild case of pneumonia and chronic bronchitis. He was hospitalized months earlier, also for pneumonia. He has a form of Parkinson's disease and uses a motorized scooter or a wheelchair for mobility.

Before being president, he served as a congressman, CIA director and Ronald Reagan's vice president.

Barbara Pierce Bush was born June 8, 1925, in Rye, New York. Her father was the publisher of McCall's and Redbook magazines. She and George H.W. Bush married when she was 19 and while he was a young naval aviator. After World War II, the Bushes moved to Texas where he went into the oil business.

Along with her memoirs, she's the author of "C. Fred's Story" and "Millie's Book," based on the lives of her dogs. Proceeds from the books benefited adult and family literacy programs. The Barbara Bush Foundation for Family Literacy began during her White House years with the goal of improving the lives of disadvantaged Americans by boosting literacy among parents and their children. The foundation partners with local programs and has awarded more than $40 million to create or expand more than 1,500 literacy programs nationwide.

Julie Finck, president of the Barbara Bush Houston Literacy Foundation, said the former first lady's passion for literacy awareness has touched many lives.

"I know many many people, including myself, said many prayers, keeping she and her family in our thoughts and prayers," Finck said.

Texas Gov. Greg Abbott released the following statement about Barbara Bush's health:

"Barbara Bush has a character that is as big, inspiring and iconic as Texas. Cecilia and I ask all Texans to join us in praying for Barbara and the entire Bush family during this time."

VIDEO: NBC's Tom Brokaw sits down with the Bushes