A senior White House official, who asked not to be identified discussing internal dynamics, said Mr. Hagin had been repeatedly targeted by others in Mr. Trump's orbit, both inside and outside the building, who questioned his loyalty given his ties to the Bush family. Mr. Trump beat Jeb Bush, the son of George Bush and brother of George W. Bush, with scathing attacks on him and his family to win the Republican nomination in 2016, and neither of the former presidents voted for him in the November election.

Mr. Trump has grown isolated within the West Wing, according to advisers, and is eager for human contact, even if that means jousting with the reporters whom he calls "fake news." He often asks staff members about whether others are leaking, and he recently told one person that "the Bushies in the White House are out to get me," according to someone with direct knowledge of the discussion.