It is the latest staff reshuffle at Trump’s White House, which has seen a high level of departures by senior aides.
Knight had announced in June that she would be leaving for a job at a banking lobby group but instead she will stay on and replace legislative affairs director Marc Short.
As deputy director of the National Economic Council, Knight was the White House’s point person on the tax cuts package that passed Congress earlier this year – the administration’s main legislative accomplishment.
She takes charge of congressional relations as the White House pushes for cuts ahead of Oct. 1, the deadline for lawmakers to pass spending bills to keep the government running for the next fiscal year.
No other major legislative initiatives are expected ahead of the Nov. 6 congressional elections, though Trump has said he wants to add to the tax cut package before that time.
The Supreme Court nomination, which is being led by White House counsel Don McGahn, is expected to be the main focus for the administration on Capitol Hill. Republicans hope Kavanaugh will be confirmed before the next Supreme Court term opens in October.
Short, a former aide to Mike Pence before he became vice president, will join the University of Virginia’s Miller Center and a Washington consulting firm, first reported by Politico.
Trump has seen record turnover among top tier staff for any modern White House, according to two political scientists who have tracked staffing since the Reagan administration.
An annual report on White House payroll released on June 29 showed 56 percent of Trump’s highest-ranking aides had left compared to the previous year’s snapshot. President Barack Obama’s White House saw 13 percent turnover among top commissioned staffers during the equivalent period.
Reporting by Roberta Rampton; Editing by Alistair Bell