WASHINGTON, Jul. 2 (NBC News) — Hunter Biden has joined meetings with President Joe Biden and his top aides since his father returned to the White House from Camp David, Maryland, on Monday evening, according to four people familiar with the matter. 

The president’s son has also been talking to senior White House staff members, these people said.

While he is regularly at the White House residence and events, it is unusual for Hunter Biden to be in and around meetings his father is having with his team, these people said. They said the president’s aides were struck by his presence during their discussions. 

A federal jury in Delaware found Hunter Biden guilty last month on gun-related charges. He remains under indictment accused of tax-related felonies, to which he has pleaded not guilty. Shortly after the jury found him guilty, he returned to his home in California.

One of the people familiar with the matter said Hunter Biden has been closely advising his father since the family gathered over the weekend at Camp David after Thursday’s debate. This person said Hunter Biden has "popped into" a couple of meetings and phone calls the president has had with some of his advisers.

Another person familiar with the matter said the reaction from some senior White House staff members has been, “What the hell is happening?”

Asked to comment, White House spokesman Andrew Bates said in a statement, “Hunter came back with the President from their family weekend at Camp David and went with the President straight into speech prep,” referring to Biden’s preparation with aides for remarks about the Supreme Court’s decision on presidential immunity. 

Hunter Biden’s presence in and around his father’s meetings comes amid questions about whether Joe Biden should continue his re-election campaign.

NBC News has reported that Hunter Biden is among the immediate family members urging the president to stay in the race. He is at the White House this week to celebrate the Fourth of July holiday with the Biden family, two people familiar with his plans said. 

Photo from NBC News