Seahawks defensive end Michael Bennett took up the cause of a missing Vietnam veteran at Sunday's game against the Philadelphia Eagles.

The controversial player invited the family of Tri-Cities native San D. Francisco to watch the game and to come down to the sidelines where they held up a sign to recognize the number of POW/MIA soldiers still in Vietnam.

Bennet has come under intense criticism for sitting during the national anthem. He surprised Francisco's family with tickets to the game for the NFL's 'My Cause, My Cleats' campaign where players showcase personal causes.

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"He called me personally, it was amazing," said Francisco's sister, Terri Francisco-Farrell. "He took the time to read my letter and go to my brother's Facebook page and read about him and he wanted to honor our family." The family said Bennett told them he recently watched a documentary about the Vietnam War and wanted to make sure those soldiers were not forgotten.

"Michael Bennett came over and shook hands with everybody and I got to hug him and even brought a little tear to my eye," Francisco-Farrell said.

"What he does that people don't see is amazing."

Francisco was shot down over enemy territory in Vietnam nearly 50 years ago. Francisco-Farrel has been pressuring the the U.S. government to excavate more crash sites in Vietnam to search for her missing brother.

Several potential burial sites were identified in 2016, and so far one and a half sites have been excavated. There are plans for the second site to finish excavation in June and July 2018. A third potential site was identified in October, and will be excavated in August and September 2018 if Francisco’s remains have not yet been found.

"I hope 50 years will be the year that he comes home and the legacy that he left I want to pass on to his granddaughters and let them know what kind of person he was," she explained. If Francisco's remains are located, they will be sent to Hawaii to be catalogued and confirmed through DNA testing.

Francisco-Farrell recently met with Secretary of Defense James Mattis and he told her the US government is committed to searching for the remains of these soldiers until they no longer have any evidence of where they might be located.