Joe Biden Remembers Son Beau on 6th Anniversary of His Death: 'This Is a Hard Day for Us'

BRENDAN SMIALOWSKI/AFP via Getty Images Joe Biden and grandson Hunter

Joe Biden is remembering his late son Beau Biden on the sixth anniversary of his death.

On Sunday morning, Biden, 78, and his wife Dr. Jill Biden visited St. Joseph's church in Wilmington, Delaware. The church, where they regularly attend services, also marks the burial site of his son Beau, the state's former attorney general who died of brain cancer in 2015 at age 46.

For the memorial mass, the Bidens were also joined by their daughter Ashley as well as Beau's son Hunter, who also sat by his grandfather's side at Veterans Memorial Park for their annual Memorial Day service later on Sunday.

"As many of you know this is a hard day for us. Six years ago today, Hunter lost his dad and I lost my son," Biden said. "If he were here, he would be here as well paying his respects to all those who gave so much for our country."

The president continued, "A lot of time passes, but you all know as well as I do that the moment that we celebrate it is the toughest day of the year. We're honored but it's a tough day. Brings back everything. So I can't thank you enough for your continued service to the country."

Biden concluded, "Your sons, your daughters, they live in your hearts and in their children as well. Thank you for allowing us to grieve together today."

Patrick Semansky/AP/Shutterstock President Joe Biden

RELATED: Tearful Joe Biden Says He Still Has Trouble Visiting Cemeteries Without 'Thinking of My Son Beau'

Patrick Semansky/AP/Shutterstock President Joe Biden

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Patrick Semansky/AP/Shutterstock President Joe Biden and grandson Hunter Biden

BRENDAN SMIALOWSKI/AFP via Getty Image President Joe Biden

BRENDAN SMIALOWSKI/AFP via Getty Images President Joe Biden

On Friday, in a speech addressing service members and their families ahead of Memorial Day, the president reflected on his son's decision to temporarily give up his attorney general seat in 2008 to join his Delaware National Guard unit in Iraq.

"He gave up the seat and had the courage to appoint a fellow who had been a Republican attorney general as attorney general while he — while he went. The proudest thing he ever did," Biden said. "He spent a year in Iraq. And it was — it was one of the great honors of his life to do it. Won the Bronze Star, the Conspicuous Service Medal, and other awards — like many of you have — but he never, ever talked about it."

"I shouldn't be talking so much about my son, but I'm not going to apologize for it," he continued. "He's like a lot of you. You do your duty. You don't expect anything for it except be a little — have — get a little respect. It deserves so much more. You deserve so much more."

RELATED: Joe Biden's History of Love and Loss and How His Late Son's Death Changed His Political Future

Brian Baer/Sacramento Bee/Tribune News Service via Getty Beau Biden (left) and Joe Biden in 2008

Both Biden and his wife have often reflected on their grief after Beau's death.

Before he was inaugurated as the 46th commander-in-chief in January, Biden told supporters in Delaware: "I only have one regret: He's not here."

And after arriving in the White House, the president immediately put up a photo of Beau behind the Resolute Desk in the Oval Office.

Beau was Delaware's attorney general from 2007 until 2015 and was deployed with the Army National Guard for a year in Iraq, from 2008 until 2009. He received a Bronze Star Medal during his tour and delegated his day-to-day duties as attorney general while serving in the Middle East.

Beau and Biden's younger son, Hunter Biden, survived the 1972 car crash that killed the president's first wife, Neilia Hunter Biden, and their infant daughter, Naomi.