Joe Biden has said that President Trump will attack his family and that a grown-up granddaughter told him that the fact that "mommy and daddy had a divorce" would be exploited in the 2020 campaign.

"This guy [Trump] is going to go after me and my family,” Biden said a fundraiser in Columbia, S.C. on Saturday before telling a story about how his grandchildren implored him to run for president. “My generic point is they know how tough it’s going to be,” Biden said to the group of about three dozen attendees gathered in the home of Dick Harpootlian, a state senator and former South Carolina state chairman of the Democratic Party.

But it also appeared to be a warning that he considered his family to be off limits in the campaign, and that press coverage of the several women who have come forward to accuse him of touching women without their consent was hurtful to his grandchildren.

Biden, 76, spoke about how one of his grandsons, Robert "Hunter" Biden II, 13, said “Pop, you have to run pop,” at a family meeting eight weeks ago. He also said how Hunter Jr. showed him a photo circulating on the internet from the funeral of his father Beau — who died in 2015 aged 46 — and said, "Pop, it says: ‘Look at Biden molesting a kid.'"

The former vice president said one grandchild told him: “Pop, I know it’s going to be mean, they’re going to say bad things about daddy. Mommy and daddy had a divorce and they’re going to really go after that."

That appeared to be a quotation from one of Hunter Biden's children. He has three daughters, Naomi, 24, Finnegan, 19, and Maisy, 18.

Hunter Biden, 49, and his wife Kathleen divorced in 2017 after it emerged that he had been having an affair with his sister-in-law Hallie after Beau's death. Kathleen claimed in divorce papers, that Hunter had spent "extravagantly on his own interests (including drugs, alcohol, prostitutes, strip clubs and gifts for women with whom he has sexual relations), while leaving the family with no funds to pay legitimate bills."

In 2014, Hunter Biden was discharged from the Navy Reserve after testing positive for cocaine during a drug test. He joined the military at the late age of 43, which required an age waiver, as well as one for a separate drug-related incident.

Beau and Hallie Biden had two children: Natalie Biden, now 14, and Hunter Jr.

It was reported this month that in 2016 Hunter Biden, who was on the board of an energy company owned by a Ukrainian oligarch, stood to benefit from the firing of the country's prosecutor general — something that his vice president father enthusiastically, and successfully, pushed.

Hunter Biden said in January that one of the lessons he took from his affair with his late brother's widow was: "Love people and find a way to love yourself." It was reported this month that Hunter Biden and Hallie Biden had split up.

[ Also read: Reporter says voters think Biden 'is genius' for visiting South Carolina]