Assistant New York Attorney General Colleen Faherty will start off the direct examination of Donald Trump Jr.

Faherty is familiar with questioning high-stakes witnesses, having led the direct examination of former Trump attorney Michael Cohen last week.

Her quick objections during Cohen's cross-examination led Trump attorney Alina Habba to accuse Faherty of trying to "throw off" her game.

A seven-year veteran of the New York attorney general's office and a former criminal defense attorney, Faherty has been a vocal presence in the courtroom since the start of the trial.

Her willingness to spar with Trump lawyer Chris Kise previously led to some heated exchanges in court, such as a sidebar when Faherty demanded Kise "be more respectful."

"No," Kise responded.

"That was rude," Faherty replied.

Donald Trump Jr. has taken the stand, where he will be the first of the former president's children to testify.

Before taking the stand, Trump Jr. sat while news photographers snapped pictures.

"I should've worn makeup," he quipped.

One week ahead of her planned testimony, Ivanka Trump has appealed Judge Engoron's decision to require her to testify in person at the Trump Organization's fraud trial.

Ivanka Trump's lawyer Bennet Moskowitz asked an appellate court to decide whether Engoron has jurisdiction to compel her testimony and whether the trial subpoenas issued by the New York attorney general were properly served.

Ivanka Trump, who is not a defendant in the case, is currently scheduled to testify next Wednesday as the final witness in the attorney general's case before the defense presents its case.

Donald Trump Jr. has arrived at the New York State Supreme Courthouse with his attorney.

Unlike his father and his brother Eric Trump -- who have visited the courtroom to watch the proceedings – Donald Trump Jr. has not stepped foot inside the courthouse for the trial until today.

A Trump Organization executive vice president, Trump Jr. is scheduled to testify in the case this afternoon.