It took 50 years, a promise in a hospital room, and one spring commencement for David Silker to become what he and his best friend once talked about, alumni brothers.

Silker returned to St. Cloud State University this spring to finish the degree he left behind in the 1970s. On graduation day, the 70-year-old walked into the auditorium as class speaker and later crossed the stage to receive his diploma.

“I always thought back, ‘What would it be like?’” David Silker said.

Silker and Bill Buttweiler met at Halenbeck Hall on the first day of classes in the fall of 1975, starting a friendship that Silker said should have seen them graduate together. But, as he put it, “life happens.”

Silker married Teresa in August of 1976 and planned to return to school after she finished her degree.

“And before you know it, children started arriving,” David said.

As family and work took priority, Silker and Buttweiler stayed close. David was in Bill’s wedding to Ann. Years later, when Ann died of Huntington’s disease, David supported his friend.

Then Buttweiler got bone cancer.

“He had bone cancer,” David said. “Unfortunately, when the cancer came back, it was too far along.”

Before Buttweiler died in December 2015, the two men spent hours talking in a hospital room at Mayo Clinic. During that conversation, Buttweiler made one request.

“He says, ‘We need to be alumni brothers,’” David recalled. “We’re brothers in life, but we need to be alumni brothers.”

After retiring as facilities operations manager at Rochester’s Mayo Civic Center, Silker went back to school instead of slowing down. On a spring Friday at St. Cloud State, Teresa helped her husband with his cap and gown as their children and grandchildren arrived. Buttweiler’s sisters, Sandy Buttweiler and Susie Sorenson, came too.

“Fifty years in the making, finally being finished,” Teresa said.

Inside the auditorium, Silker entered first as the announcer read: “David B. Silker, your class speaker.”

“Thank you,” he said before telling fellow graduates how he got there.

“Time is fleeting, but friendships are eternal,” David told them. “Today, Bill and I are alumni brothers.”

After the ceremony, Silker told Sandy Buttweiler and Susie Sorenson that his friend had been with him.

“He was with me,” David told them.

The three showed matching infinity symbol tattoos on their lower arms.

“He always said, ‘I’ll love you to infinity and back,’” David said.

The next morning, David and Teresa Silker, their son Chad, Sandy Buttweiler and Susie Sorenson went to Bill Buttweiler’s grave at Sunset Cemetery in St. Anthony. Silker knelt with diploma in hand and spoke to his friend’s headstone.

“We did it together, buddy,” David told Bill, “My friend, my brother.”

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