In Memory: Sully Has The Watch.

Sully, the service dog of former President George H.W. Bush, spent Sunday night lying before Bush’s flag-draped casket in Houston.

Jim McGrath, spokesman for the Bush family, tweeted out a photo on Sunday night, captioning it “mission complete.”

CNN reported that Sully would travel with the casket to Washington, D.C., where several days of remembrance ceremonies are being held.

Sully, a 2-year-old yellow Labrador retriever, is named after the pilot Chesley “Sully” Sullenberger III, who on Jan. 15, 2009, landed a passenger plane in the Hudson River after hitting a flock of geese. He was portrayed by Tom Hanks in a movie about the incident.

Sully became the late president’s service dog in June, a couple of months after former first lady Barbara Bush died.

The yellow Lab was trained by America’s VetDogs, which places service dogs and guide dogs with veterans, active-duty service members and first responders.