Bush twins to release memoir

George and Barbara Bush with their four boys: George W., Neil, Jeb and Marvin.

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George Herbert Walker Bush poses with his wife Barbara during his campaign for Congress in the 1960's. Born 12 June 1924 in Milton, Massachussetts, George Bush Yale graduated with a degree in Economics in 1948, made a fortune drilling oil before entering politics in 1964. US Congressman from Texas (1966-1970), ambassador to the United nations (1971-1974), Special Envoy to China (1974-1975), Republican National Chairman (1975-1976), Central Intelligence Agency (CIA) director (1976-1977), vice president of the US (1981-1959) George Bush is eventually elected president of the US 08 November 1988 against Democratic nominee Michael Dukakis.

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Pres. George Bush and First Lady Barbara (in sunglasses) riding in their Cigarette boat Fidelty w. an unident. man.

(Photo by Susan Biddle/White House/The LIFE Picture Collection/Getty Images)

George Herbert Walker Bush poses with his wife Barbara in Beijing in 1974. Born 12 June 1924 in Milton, Massachussetts, George Bush Yale graduated with a degree in Economics in 1948, made a fortune drilling oil before entering politics in 1964. US Congressman from Texas (1966-1970), ambassador to the United nations (1971-1974), Special Envoy to China (1974-1975), Republican National Chairman (1975-1976), Central Intelligence Agency (CIA) director (1976-1977), vice president of the US (1981-1959) George Bush is eventually elected president of the US 08 November 1988 against Democratic nominee Michael Dukakis.

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President Gerald R. Ford and Barbara Bush watch as Justice Potter Stewart swears in George H.W. Bush as the new Director of the CIA, at CIA HQ in Langley, Virginia, January 26, 1976. The outgoing Director William Colby is at the left in the background.

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Republican Presidential candidate George Bush, wearing a t-shirt referencing his son George W. Bush, stands with his wife Barbara November 1978 in Texas, USA. Bush is campaigning for the presidential primary elections.

(Photo by Dirck Halstead/Liaison)

Republican Presidential candidate George Bush looks at his wife Barbara November 1, 1978 in Hoston, TX. Bush is campaigning for the presidential primary elections.

(Photo by Dirck Halstead/Liaison)

Vice President George Bush and his wife Barbara attend the 1988 Republican National Convention in New Orleans. Bush won the 1988 United States presidential election over democratic challenger Michael Dukakis.

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Barbara Bush stands with Vice President George Bush, who is holding their grandchild during the 1988 Republican National Convention in New Orleans, Louisiana.

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Pres. & signature pearls wearing Barbara Bush interacting affectionately during awards ceremony in WH East Rm.

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President George H.W. Bush and First Lady Barbara Bush stand at the South Portico of the White House awaiting the arrival of Diplomatic guest.

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Pres. & Barbara Bush waving before boarding pres. plane, leaving Italy.

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President George Bush and Barbara Bush during Chris Evert Celebrity Tennis Classic at Boca Raton Resort & Club in Boca Raton, Florida, United States.

(Photo by Ron Galella, Ltd./WireImage)

George H.W. Bush and his wife Barbara celebrate with George W. Bush and his wife Laura, after the networks declared George W. Bush the winner of the US presidential election.

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Former U.S. President George H.W. Bush and former first lady Barbara Bush attend a portrait unveiling at the George Bush Library April 21, 2003 in College Station, Texas. A painting of the father/son presidents went on display.

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Barbara Bush and her husband 41st President George H Bush watch Andy Roddick play Rainer Schuettler of Germany during the Tennis Masters Cup November 13, 2003 at the Westside Tennis Club in Houston, Texas.

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Former First Lady Barbara Bush, right, and another person react shortly after former President George H. W. Bush received a lapel pin referencing director Michael Moore on the second day of the Republican National Convention in New York, August 31, 2004.

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American politician (and future US President) George HW Bush speaks at an event during his campaign for the Republican Presidential nomination, Iowa, January 1980. His wife, future First Lady Barbara Bush, stands beside him.

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Former US President George H.W. Bush (L) with wife, former First Lady Barbara Bush, and grand-daughters Barbara (L) and Jenna, wave as they walk through the Rotunda on Capitol Hill 20 January, 2005. With a pledge to battle terrorism and promote democracy around the world, US President George W. Bush was to launch his new term today under an unprecedented security blanket and a dusting of snow. Bush, 58, was to be sworn in outside the US Capitol at noon (1700 GMT), in the 55th US presidential swearing-in and the first since the September 11, 2001 terrorist attacks that transformed his time in office.

(ROBERT SULLIVAN/AFP/Getty Images)

Barbara Bush (L) wipes water off the shoulder of her husband former US president George Bush (R) during the inauguration of the William J. Clinton Presidential Center in Little Rock, Arkansas, 18 November 2004. Constant rain fell during the opening ceremony of the center which contains some 76.8 million pages of paper documents, 1.85 million photographs and over 75,000 museum artifacts from Clinton's eight years in the White House.

(ROBERTO SCHMIDT/AFP/Getty Images)

NBC NEWS -- 'Ronald Reagan First Presidential Inauguration'

Pictured: (l-r) U.S. Vice President George Bush, Second Lady Barbara Bush during the first inauguration of President Ronald Reagan on January 20, 1981 in Washington D.C.

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Vice President George Bush stands with his wife Barbara August 1983 in Kennebunkport, ME. Bush is vacationing in Maine with his family.

(Photo by Cynthia Johnson/Liaison)

Former President George H.W. Bush reacts alongside Barbara Bush as their son, President George W. Bush delivers the commencement address during the Texas A&M University graduation ceremony at Reed Arena in College Station, Texas, on December 12, 2008.

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Former President George H.W. Byush and Mrs. Barbara Bush
 

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Former US president George H.W. Bush and his wife Barbara arrive for the inauguration of Barack Obama as the 44th US president at the Capitol in Washington on January 20, 2009.

(PAUL J. RICHARDS/AFP/Getty Images)

Former US president George H.W. Bush (C) and his wife Barbara (L) step off Air Force One with their grandaughter Barbara (R), the daughter of US President George W. Bush, step off Air Force One May 11, 2008 upon arrival at Andrews Air Force Base in Maryland. US President George W. Bush and his family were returning to Washington, DC after attending the wedding of his daughter Jenna at his Crawford, Texas ranch.

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US President George W. Bush (R), his mother Barbara Bush (2R), former President George H. W. Bush (C), First Lady Laura Bush (3L) and her mother Jenna Welch (2r) wave as they arrive at Fort Hood, Texas, for Easter Service 08 April 2007.

(JIM WATSON/AFP/Getty Images)

Former first lady Barbara Bush waives to friends as former President George H.W. Bush, right, and former Secretary of State James A. Baker III look on during a baseball game between the Chicago Cubs and the Houston Astros at Minute Maid Park on April 13, 2011 in Houston, Texas.

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Former President George H.W. Bush and wife Barbara watch the game between the Colorado Rockies and the Houston Astros on Opening Day at Minute Maid Park on April 6, 2012 in Houston, Texas.

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Film Subject President George H.W. Bush and his wife, Mrs. Barbara Bush attend the HBO Documentary special screening of '41' on June 12, 2012 in Kennebunkport, Maine.

(Photo by Michael Loccisano/Getty Images for HBO)

From left US President Barack Obama, former first lady Barbara Bush, former US President George H. W. Bush and former US President George W. Bush say an opening prayer during a dedication ceremony at the George W. Bush Library and Museum on the grounds of Southern Methodist University April 25, 2013 in Dallas, Texas. The Bush library, which is located on the campus of Southern Methodist University, with more than 70 million pages of paper records, 43,000 artifacts, 200 million emails and four million digital photographs, will be opened to the public on May 1, 2013.

(BRENDAN SMIALOWSKI/AFP/Getty Images)

Former President George H.W. Bush and Former First Lady Barbara Bush meet with Andrea Bocelli and wife Veronica Bocelli before his concert at Toyota Center on December 11, 2016 in Houston, Texas.

(Photo by Bob Levey/Getty Images)

Former President George H.W. Bush (R) and former First Lady Barbara Bush give the thumbs-up from inside the presidential viewing stand overlooking Pennsylania Avenue during the Inaugural Parade 20 January 2005 in Washington, DC. In the 55th US presidential inauguration and the first since the September 11, 2001 attacks, Bush solemnly took the oath of office and declared that defeating terrorism required embracing a global mission to foment democracy.

(STAN HONDA/AFP/Getty Images)

Former First Lady Barbara Bush and former President George H.W. Bush look on during a game between the Gonzaga Bulldogs and the Duke Blue Devils during the South Regional Final of the 2015 NCAA Men's Basketball Tournament at NRG Stadium on March 29, 2015 in Houston, Texas. Duke won 66-52.

(Photo by Lance King/Getty Images)

Former President George H.W. Bush and former First Lady Barbara Bush are introduced prior to game three of the American League Division Series between the Houston Astros and the Kansas City Royals at Minute Maid Park on October 11, 2015 in Houston, Texas.

(Photo by Bob Levey/Getty Images)