The news was confirmed on Thursday when Michael Cohen, President Trump's former attorney, pleaded guilty to lying about the proposed deal to Congress. Multiple sources confirmed to Yahoo that Ivanka, a senior White House advisor, and Don Jr., the president's oldest son, worked on the project. A "separate source familiar with the investigation" said Mueller had asked questions about their work.
In Mueller's charging documents against Cohen, Cohen reportedly lied that he had "briefed family members" of Trump's who worked at the Trump Organization about the building project. Both Ivanka and Don Jr. were then executives at the organization; Ivanka has given up her role since joining the White House.
The duo reportedly ended their attempts in 2013, and their efforts were separate from Cohen's. "They were not looking at any other deals after that," the source said. They were, however, aware of Cohen's efforts. "Michael was looking at that deal. Don and Ivanka knew about it and Don testified to the Senate Judiciary Committee that he was peripherally aware of it," the source said. "That’s why we’re so perplexed Cohen would lie about briefing them, because no one’s ever disputed that they knew he was looking at it."