Bush will be buried next to wife Barbara, who died in April, and daughter Robin, who died of leukemia aged three.
On Monday, the former president's body will be transported from a funeral home in Texas to the U.S. Capitol in Washington, D.C., for a short arrival ceremony.
The casket will then be transported to the cathedral for the funeral service - the fourth there of a former president. The coffin will be flown from Texas to the Capitol on board Air Force One, and then back on Wednesday, and Sully will be there every step of the way. The rest of the Bush family is expected to be at Joint Base Andrews when the body arrives. A departure ceremony will be held at the Ellington Field Joint Reserve Base near Houston at 10:30 a.m. local time.
Current president Donald Trump will attend the funeral with most of the remaining living presidents, despite having frost relations with all.
A photo of George HW Bush's service dog lying downbeat besides the casket of his old master on Sunday has spread across social media, causing an outpouring of emotion.
Trump previously declared December 5 as a national day of mourning to honor the 41st president.More news: Chiefs Kareem Hunt Attacks and Kicks Woman in Hotel Hallway
A public viewing of Bush's casket will be held at the church from 1.45pm.
Sully the dog will be travelling with the casket on the flight from Texas to Washington DC on Monday. The locomotive has been painted the colors of the Air Force One plane used during his presidency and bears the number "4141" in honour of the 41st president. And if you happen to live in our near the Texas towns of Hufsmith, Pinehurst, Magnolia, Todd Mission, Stoneham, Navasota, Millican, and Wellborn, you may be able to catch the train carrying Bush's remains from Houston, Texas to College Station, Texas, where Bush's remains will be interred at his Presidential Library & Museum. He died Friday in Houston at age 94.
Shortly before leaving the service, he married his 19-year-old sweetheart, Barbara Pierce, and forged a 73-year union that was the longest presidential marriage in US history until her death. Thousands of mourners paid respects at a weekend candlelight vigil at a nearby pond, and others contributed to growing flower memorials at Bush statues at both the library and a park in downtown Houston.
Ceremonies at the presidential library will include a missing man formation flyover.