Transcript for Timing of top Trump aide's resignation raises questions

We begin with that shake-up at the white house. His personal aide hope hicks has redesigned and Jared Kushner facing a barrage of bad news. His attorney general Jeff sessions is pushing back against the president's public attacks. We want to begin with hicks' departure who joins a long list of trump loyal IFS who have come and gone since last year and Cecilia Vega has all the latest. Good morning. Reporter: Some stunning developments here. Good morning to you. Right after this news broke, hicks gave a tearful thank you to her communications team. This comes just 24 hours after that bombshell admission to congress ha she told white lies on behalf of the president of the United States but the white house says that has nothing to do with the timing of her departure. They say it's just coincidence. Few in the white house inner circle have been closer or more loyal to president trump. Now, hope hicks is a tremendously talented person. She started off with us right from day one. Reporter: But this morning, the 29-year-old communications director is out. The fourth communications director to resign in the trump administration. In a statement hope hicks saying, there are no words to adequately express my gratitude to president trump. The official line from the white house, hicks has been planning her departure for months and leaving to spend more time with her family but comes after that stunning admission to congressional investigators this week that she occasionally tells white lies on behalf of the president. Any collusion. Reporter: She is a central figure in thesia investigation questioned for two days by special counsel Robert Mueller over a involvement in crafting the president's response to that now infamous trump tower meeting between don junior and the Russians and was at the center of the firestorm over the departure of former staff secretary rob porter ousted amid domestic violence allegations. Porter and hicks were dating and she helped develop the administrati administration's difference of him when the news broke. The president praised his outgoing aide in a statement saying she is as smart and thoughtful as they come. A truly great person. I will miss having her by my side. She became one of the pose powerful players in the trump white house. By the president's side through the campaign. Before that in trump tower as an assistant to the billionaire businessman. A former model she joined the family working on Ivanka Trump's fashion line joining the list of aides who left the west wing in this young administration. And hicks isn't leaving for a few weeks but with her gone this leaves a stunning lack of confidants in the president's inner circle. His former golf caddie is the last man standing from the original team of his campaign, only Jared and ivanka are the -- after Jared and ivanka there is literally no one left. And, Cecilia, the communications director doesn't capture what her role was. She was basically in every meeting with the president inside the white house and translated him to other staffers across the government. He would often look her way in meetings to make sure what he was saying was on track. Can anyone fill that role? Reporter: Well, probably not to be honest, George. Her office was right outside the president's oval office. This was someone among his most trusted confidantes outside of his own family. With her gone there is a real fear that president trump is becoming increasingly isolated. As you say she could keep him calm and rein in some of these fly by the seat of his pants tendency, with her gone aides are worrying what is to come. President trump's son-in-law

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