Steve Bannon may have been prophetic when he told Michael Wolff that Robert Mueller’s “path to fucking Trump” would run right through Jared Kushner. As CNN reported Monday, the special counsel’s interest in Kushner has now expanded beyond his many contacts with Russian officials to include his family’s real-estate empire. The implication, as Bannon predicted, is that Mueller is seeking dirt that could explain any potential collusion between the Trump campaign and Russia—and provide leverage to get Kushner to flip on other members of the Trump family.

F.B.I. investigators are particularly interested in Kushner’s efforts to secure financing for 666 Fifth Avenue, the Midtown skyscraper that Kushner purchased over a decade ago for nearly $1.8 billion in debt, and which has become a massive albatross for the family. During the transition, Kushner reportedly held conversations with investors including Chinese insurance giant Anbang, but the deal stalled in March. Mueller’s team is also said to be interested in conversations Kushner and his father held with Qatari investor and former prime minister Hamad bin Jassim al-Thani in 2015 and 2016, which also collapsed. (“Another anonymous source with questionable motives now contradicts the facts,” Kushner’s attorney, Abbe Lowell, told CNN. “In all of Mr. Kushner’s extensive cooperation with all inquiries, there has not been a single question asked nor document sought on the 666 building or Kushner Co. deals.” Kushner Cos. declined a request for comment.)

The question of Kushner’s personal debts, and his various financial entanglements, has long been a cause for concern among his critics. While Kushner and his wife, Ivanka Trump, have partially divested themselves of their family businesses, both retain financial interests and hold millions of dollars in debt. Last week, it was reported that the couple had revised their disclosure form to indicate their debts are in the range of $31 million to $155 million, up from $19 million and $98 million last June. The increase coincides with Kushner Cos.’ reported financial troubles, as the company races to find investors to help pay the $1.2 billion mortgage it still owes on 666 Fifth. Among the foreign contacts Mueller is said to be investigating is Kushner’s Trump Tower meeting with Sergey Gorkov, the chairman of Russian state-run Vnesheconombank, during the presidential transition in December 2016. (Kushner told congressional investigators last year that he had taken the meeting with Gorkov, whose bank was blacklisted by the Obama administration, because Gorkov was said to be someone “who could give insight into how Putin was viewing the new administration and best ways to work together.”)

Mueller’s interest in those meetings may be one of the reasons that Kushner has struggled to secure a permanent security clearance in the White House. The background check for the president’s son-in-law has dragged on for months as he has submitted multiple updates to his security and financial disclosure forms, reportedly frustrating Chief of Staff John Kelly. On Friday, Kelly announced that some White House staffers with interim security clearances would no longer be allowed access to classified information—a move that one senior official told The Washington Post was a “bulls-eye” aimed at Kushner. How the senior White House adviser can continue to oversee his broad portfolio of issues—which includes brokering peace in the Middle East and acting as a point person for U.S. relationships with China and Saudi Arabia—remains to be seen. In the meantime, the Post reports, Kushner has issued more requests for classified intelligence than any other White House employee, apart from National Security Council staff.