NEW YORK — Former President George H.W. Bush's service dog Sully H.W. Bush and "Miracle on the Hudson" hero Capt. Chesley "Sully" Sullenberger met for the first time Thursday on NBC's "Today" show.

Sully the dog was by his companion's side until the very end, providing President Bush with faithful comfort. While the two only knew each other for five months, Sully was there for Bush when he needed him the most, arriving a month after he had lost his wife and soulmate of 73 years, Barbara Bush.

Sully spent most of his time with President Bush in Kennebunkport, Maine, becoming an integral part of the family. Jenna Bush Hager's kids Mila and Poppy even began to think Sully was theirs — and he let them believe it, she said.

"The adults knew that it wasn't forever," Bush Hager said on "Today," talking about Sully the dog's time with the family. "It's hard, though. There was a moment my daughters thought Sully had passed away. They said, well, 'did he go with Great Gampy?' Because he was always with him. I think we sometimes don't think of service dogs as helping those that are in their final months but the comfort that this dog provided my whole family."

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"Sully, we miss you terribly, we thank you for your service, and your devotion to our Gampy," Bush Hager said. "And, yes. Mission complete."

Both President Bush and Sully shared the virtue of service. The 41st president was the Navy’s youngest pilot during World War II, and Sully is a service dog with America's VetDogs, a nonprofit providing assistance to military veterans.

So it's only fitting Sully was named after another person who served.

Capt. Sully was a captain in the Air Force before becoming a commercial pilot. In 2009, he safely landed an Airbus A320 on the Hudson River after it had struck a flock of geese above New York City, saving all 155 onboard.

On "Today," Capt. Sully wore socks depicting a yellow lab, a salute to President Bush, who was well known for his foot garment wardrobe.

Bush Hager said her family initially made plans to meet Capt. Sully over the summer in Maine, but President Bush's health began to decline. Bush had not met Capt. Sully before and was regretful he wasn't able to shake his hand.

In an incredibly heartwarming moment, soon after Sully H.W. Bush was called on to the set by Bush Hager, Capt. Sully used commands to shake his paw.

Capt. Sully said it was an honor to have Sully named after him.

Bush Hager's kids joined the set at the end and reunited with the service dog.

Sully H.W. Bush begins his new job next week as a facility dog at Walter Reed National Military Medical Center in Bethesda, Maryland.