Secretary of State Marco Rubio “can’t wait” until Karoline Leavitt resumes her duties after subbing in for the White House Press Secretary at the podium. Leavitt, who has held the role since the start of President Donald Trump’s second term, went on maternity leave April 27. Her daughter, Viviana, was born May 1 to Leavitt, 28, and her husband, Nicholas Riccio, 60. The couple’s son, Nicholas, “Niko” will turn two in July. Rubio subbed in for Leavitt at a raucous press briefing on May 5 where he answered questions from reporters for nearly an hour. "Karoline is irreplaceable...I was just a pinch-hitter,” Rubio told Fox News anchor Sean Hannity on Air Force One Wednesday as he traveled with Trump to China for a summit with President Xi Jinping . “We can't wait until Karoline gets back." Leavitt has not said when she will return from maternity leave.…