Along with Donald Trump and Melania Trump, former USA presidents Jimmy Carter, Bill Clinton and Barack Obama were seated in the first row of the Washington National Cathedral along with their spouses when Bush, the 43rd president took a moment to shake each of their hands.
Mourners lined up to enter the Capitol beginning Monday evening for the public viewing.
House Speaker Paul Ryan said "here lies a great man, a gentle soul. My opinion of him went up seeing how he conducted himself as a statesman afterward". "My thoughts and prayers are with President Bush's family and the American people". "He seemed like a honest and decent man and you couldn't argue with his qualifications".
It was a truly heartbreaking scene, just days after Bush's passing on Saturday 1 December, when a photo emerged of Sully laying by his former master's casket - now people have been left in tears again as the dog showed up to pay his respects, dressed in his finest therapy dog vest adorned with the Stars and Stripes.
Bush's beloved service dog, Sully, faithfully joined his companion on his final journey to Washington, DC and on Tuesday sat at attention a few moments next to the casket as the President lay in state at the U.S. Capitol rotunda.
There were chills for sure in Smithtown, where Sully was trained by America's VetDogs.
Like Bush, Dole is a World War II veteran. Bush, a Navy pilot, survived a bail-out from his stricken aircraft over the Pacific and an earlier crash landing. He arrived in the Capitol rotunda in a wheelchair pushed by an aide.
Post Office, Stock Market Among Closures for Tomorrow's Holiday Honoring Former President Bush
Dignitaries came forward on Monday to honor the Texan whose service to his country extended three quarters of a century, from World War II through his final years as an advocate for volunteerism and relief for people displaced by natural disaster. Bush died last April and Robin died from leukemia at just four years old.
Mr Trump's relationship with the Bush family has been tense.
Mr Trump repeatedly criticised Mr Bush Jnr's policies, not least his Middle Eastern military intervention, and defeated Jeb Bush, his brother, in the 2016 race for the Republican presidential nomination, dubbing him "low-energy Jeb".
Cannon fire roared again outside the Capitol as the sun sank and the younger Mr Bush stood with his hand over his heart, watching the casket's procession up the steps.
An invitation-only funeral service, which the Trumps will attend, will take place at Washington's National Cathedral. He was a familiar presence in Washington: a congressman in the late 1960s, then Central Intelligence Agency director, envoy to China and Republican Party chairman.
After Thursday's private services, the former president will be taken by a train, pulled by an engine commissioned in his honor, 120 kilometers north to the city of College Station for burial at his presidential library on the grounds of Texas A&M University.More news: World's first baby born via womb transplant from dead donor
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