A heartbreaking photo was posted on the dog's social media account Sunday night showing him sleeping in front of the flag-draped casket of his late master, George H.W. Bush.
America's 41st president died late Friday at his home in Houston.
The socks feature a formation of jets, which are meant to honor his lifetime of service that started when he became a naval aviator at 18 years old. Even after Bush died, though, Sully still looked out for his appointee, whom he began to serve in June, just months after Bush's wife, Barbara Bush, died in April.
"He added: "A lovely day In Texas - 'ceiling and visibility unlimited, ' Mr. President".
The Supreme Court is delaying arguments by a day while a national day of mourning is held for former President George H.W. Bush.
David J. Phillip Pool AP
Instead, the Bush family has lined up four people to give eulogies - including Bush's son President George W. Bush.
The former president's body will arrive in Washington, D.C., today to lie in state in the U.S. Capitol Rotunda.
He died aged 94 in Houston, Texas.
To honor the former president, the worldwide nonprofit Points of Light, founded by Bush, invited the public to celebrate Bush by giving a day of service in his memory.
President Trump and first lady Melania Trump plan to attend the ceremony Wednesday morning at the National Cathedral in Washington.More news: NBA Kawhi Leonard: 'When You Stop Playing They Forget How You Lead'