Former president George H.W. Bush with Patrick, the child of a Secret Service agent, in Kennebunkport, Maine, on July 24, 2013. (Barbara Bush/Office of George Bush/AP)

George H.W. Bush sat outside near a flower garden in Kennebunkport, Maine, in 2013, holding a 2-year-old child. The pair wore matching blue polo shirts and khaki pants — and sported the same hairstyle.

Bush had learned that the boy, the son of an agent on his Secret Service detail, had leukemia. The toddler had lost his hair, and to show their support, members of the detail were planning to shave their heads.

So Bush did, too.

The former president’s wife, Barbara Bush, snapped a picture of them, and it soon went viral.

“When little Patrick got leukemia, a lot of the agents shaved their heads,” Bush explained to his granddaughter Jenna Bush Hager, a contributing correspondent for NBC’s “Today” show. “I said, ‘Well, why not me?’ It was the right thing to do.”

“They’re a wonderful group of people,” Bush added at the time. “They’re like family with us.”

The agents thought of Bush the exact same way.

The Secret Service re-shared the touching photo Tuesday on Twitter, referring to the 41st president by his code name, “Timberwolf.” The agency said it “wanted to share a memory” the day before his funeral at Washington National Cathedral.

The young boy’s battle with leukemia hit close to home for the former president and his wife. He and Barbara lost their 3-year-old daughter Robin to the disease in 1953.

Following the gesture in 2013, the boy’s family said in a statement to “Today” that they were “humbled and honored by the support and generosity that President and Mrs. Bush and our Secret Service family have shown towards our son."

Three years later, Bush posted the photo on his personal Twitter account, along with an updated one showing the boy several years older — with a full head of hair.

“Incredibly #thankful that my friend Patrick, the courageous young man (with hair!) to my left, is feeling and doing much better these days,” he wrote at the time.

CNN analyst Jonathan Wackrow, a former Secret Service agent, remembered that moment Tuesday in an op-ed for the network, saying that members of the security detail considered Bush family.

Wackrow wrote:

Over the 38 years that members of the Secret Service had the privilege of protecting Bush and his family, he, in turn, became part of the Secret Service family. Each day, he led by example, teaching us how to live with dignity and respect.

With his passing, a part of the soul of the Secret Service is gone as well. However, it will never be forgotten. Instead, his legacy will live on in the hearts of the countless people he touched.

It was an honor and privilege to protect you, Timberwolf.

On Friday, a day after the former president was buried on the grounds of his presidential library at Texas A&M University in College Station, the Secret Service posted on Twitter that his security detail had completed its final mission.

“Timberwolf’s Detail concluded at 0600 hours on December 7, 2018 with no incidents to report at the George Bush Presidential Library — College Station, Texas. God speed Former President George H.W. Bush — you will be missed by all of us.

“— Bush Protective Division.”

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