As the campaign enters its final stretch, some of Donald Trump's children are showing signs of impatience and struggling to stay on message.

In the past 24 hours, Ivanka Trump and Donald Trump Jr. have cut off interviews when pressed for answers on tough questions. Trump Jr. strayed from the campaign's talking point about the Republican nominee's tax returns -- that they'll be released once an IRS audit concludes -- when he said unveiling the documents would "detract" from his father's message.

And Trump Jr. caused a firestorm when, during a Thursday interview with a Philadelphia radio station, he raised the specter of the Holocaust by saying if Republicans acted like Hillary Clinton, the media would be "warming up the gas chamber." The campaign later said Trump Jr. was referring to capital punishment, though the Clinton campaign quickly seized on the remarks.

"The particular wording is extremely insensitive, divisive and probably pretty consistent with the type of rhetoric he heard around the house growing up," Clinton campaign chair John Podesta told reporters on a conference call.

Representatives for the Trump campaign didn't respond to requests for comment on this story.

The developments are notable because Trump's children are typically his best surrogates. Ivanka, in particular, often softens Trump's image and the children are known for exerting power behind the scenes and bringing discipline to the freewheeling campaign.

The influence of Trump's children was seen in the firing of former campaign manager Corey Lewandowski. His children personally vetted vice presidential contenders this summer. And at the Republican National Convention, his four adult children -- Ivanka, Don Jr., Eric and Tiffany -- each delivered speeches that sought to show more human sides of their father.

Photos: Donald Trump's rise Photos: Donald Trump's rise President-elect Donald Trump has been in the spotlight for years. From developing real estate and producing and starring in TV shows, he became a celebrity long before winning the White House. Hide Caption 1 of 37 Photos: Donald Trump's rise Trump at age 4. He was born in 1946 to Fred and Mary Trump in New York City. His father was a real estate developer. Hide Caption 2 of 37 Photos: Donald Trump's rise Trump, left, in a family photo. He was the second-youngest of five children. Hide Caption 3 of 37 Photos: Donald Trump's rise Trump, center, stands at attention during his senior year at the New York Military Academy in 1964. Hide Caption 4 of 37 Photos: Donald Trump's rise Trump, center, wears a baseball uniform at the New York Military Academy in 1964. After he graduated from the boarding school, he went to college. He started at Fordham University before transferring and later graduating from the Wharton School, the University of Pennsylvania's business school. Hide Caption 5 of 37 Photos: Donald Trump's rise Trump stands with Alfred Eisenpreis, New York's economic development administrator, in 1976 while they look at a sketch of a new 1,400-room renovation project of the Commodore Hotel. After graduating college in 1968, Trump worked with his father on developments in Queens and Brooklyn before purchasing or building multiple properties in New York and Atlantic City, New Jersey. Those properties included Trump Tower in New York and Trump Plaza and multiple casinos in Atlantic City. Hide Caption 6 of 37 Photos: Donald Trump's rise Trump attends an event to mark the start of construction of the New York Convention Center in 1979. Hide Caption 7 of 37 Photos: Donald Trump's rise Trump wears a hard hat at the Trump Tower construction site in New York in 1980. Hide Caption 8 of 37 Photos: Donald Trump's rise Trump was married to Ivana Zelnicek Trump from 1977 to 1990, when they divorced. They had three children together: Donald Jr., Ivanka and Eric. Hide Caption 9 of 37 Photos: Donald Trump's rise The Trump family, circa 1986. Hide Caption 10 of 37 Photos: Donald Trump's rise Trump uses his personal helicopter to get around New York in 1987. Hide Caption 11 of 37 Photos: Donald Trump's rise Trump stands in the atrium of the Trump Tower. Hide Caption 12 of 37 Photos: Donald Trump's rise Trump attends the opening of his new Atlantic City casino, the Taj Mahal, in 1989. Hide Caption 13 of 37 Photos: Donald Trump's rise Trump signs his second book, "Trump: Surviving at the Top," in 1990. Trump has published at least 16 other books, including "The Art of the Deal" and "The America We Deserve." Hide Caption 14 of 37 Photos: Donald Trump's rise Trump and singer Michael Jackson pose for a photo before traveling to visit Ryan White, a young child with AIDS, in 1990. Hide Caption 15 of 37 Photos: Donald Trump's rise Trump dips his second wife, Marla Maples, after the couple married in a private ceremony in New York in December 1993. The couple divorced in 1999 and had one daughter together, Tiffany. Hide Caption 16 of 37 Photos: Donald Trump's rise Trump putts a golf ball in his New York office in 1998. Hide Caption 17 of 37 Photos: Donald Trump's rise An advertisement for the television show "The Apprentice" hangs at Trump Tower in 2004. The show launched in January of that year. In January 2008, the show returned as "Celebrity Apprentice." Hide Caption 18 of 37 Photos: Donald Trump's rise A 12-inch talking Trump doll is on display at a toy store in New York in September 2004. Hide Caption 19 of 37 Photos: Donald Trump's rise Trump attends a news conference in 2005 that announced the establishment of Trump University. From 2005 until it closed in 2010, Trump University had about 10,000 people sign up for a program that promised success in real estate. Three separate lawsuits -- two class-action suits filed in California and one filed by New York's attorney general -- argued that the program was mired in fraud and deception. Trump's camp rejected the suits' claims as "baseless." And Trump has charged that the New York case against him is politically motivated. Hide Caption 20 of 37 Photos: Donald Trump's rise Trump attends the U.S. Open tennis tournament with his third wife, Melania Knauss-Trump, and their son, Barron, in 2006. Trump and Knauss married in 2005. Hide Caption 21 of 37 Photos: Donald Trump's rise Trump wrestles with "Stone Cold" Steve Austin at WrestleMania in 2007. Trump has close ties with the WWE and its CEO, Vince McMahon. Hide Caption 22 of 37 Photos: Donald Trump's rise For "The Apprentice," Trump was honored with a star on the Hollywood Walk of Fame in January 2007. Hide Caption 23 of 37 Photos: Donald Trump's rise Trump appears on the set of "The Celebrity Apprentice" with two of his children -- Donald Jr. and Ivanka -- in 2009. Hide Caption 24 of 37 Photos: Donald Trump's rise Trump poses with Miss Universe contestants in 2011. Trump had been executive producer of the Miss Universe, Miss USA and Miss Teen USA pageants since 1996. Hide Caption 25 of 37 Photos: Donald Trump's rise In 2012, Trump announces his endorsement of Republican presidential candidate Mitt Romney. Hide Caption 26 of 37 Photos: Donald Trump's rise Trump speaks in Sarasota, Florida, after accepting the Statesman of the Year Award at the Sarasota GOP dinner in August 2012. It was shortly before the Republican National Convention in nearby Tampa. Hide Caption 27 of 37 Photos: Donald Trump's rise Trump appears on stage with singer Nick Jonas and television personality Giuliana Rancic during the 2013 Miss USA pageant. Hide Caption 28 of 37 Photos: Donald Trump's rise In June 2015, during a speech from Trump Tower, Trump announced that he was running for President. He said he would give up "The Apprentice" to run. Hide Caption 29 of 37 Photos: Donald Trump's rise Trump -- flanked by U.S. Sens. Marco Rubio, left, and Ted Cruz -- speaks during a CNN debate in Miami on March 10. Trump dominated the GOP primaries and emerged as the presumptive nominee in May. Hide Caption 30 of 37 Photos: Donald Trump's rise The Trump family poses for a photo in New York in April. Hide Caption 31 of 37 Photos: Donald Trump's rise Trump speaks during a campaign event in Evansville, Indiana, on April 28. After Trump won the Indiana primary, his last two competitors dropped out of the GOP race. Hide Caption 32 of 37 Photos: Donald Trump's rise Trump delivers a speech at the Republican National Convention in July, accepting the party's nomination for President. "I have had a truly great life in business," he said. "But now, my sole and exclusive mission is to go to work for our country -- to go to work for you. It's time to deliver a victory for the American people." Hide Caption 33 of 37 Photos: Donald Trump's rise Trump faces Democratic nominee Hillary Clinton in the first presidential debate, which took place in Hempstead, New York, in September. Hide Caption 34 of 37 Photos: Donald Trump's rise Trump apologizes in a video, posted to his Twitter account in October, for vulgar and sexually aggressive remarks he made a decade ago regarding women. "I said it, I was wrong and I apologize," Trump said, referring to lewd comments he made during a previously unaired taping of "Access Hollywood." Multiple Republican leaders rescinded their endorsements of Trump after the footage was released. Hide Caption 35 of 37 Photos: Donald Trump's rise Trump walks on stage with his family after he was declared the election winner on November 9. "Ours was not a campaign, but rather, an incredible and great movement," he told his supporters in New York. Hide Caption 36 of 37 Photos: Donald Trump's rise Trump is joined by his family as he is sworn in as President on January 20. Hide Caption 37 of 37

Ivanka Trump used her convention speech to wade into policy, making a case to women by arguing for paid maternity leave and equal pay. Her primetime Thursday night introduction of her father was well-received -- particularly as she revealed a softer side of the billionaire businessman that no other speaker or surrogate had been able to show before.

And after a week in which Republicans largely focused on Clinton's deficiencies rather than on Trump's attributes and personal story, Ivanka Trump warmed up the crowd by offering a new window into the Republican nominee. She urged viewers to give her father a second look by saying that "if It's possible to be famous and not really well-known, that describes the father who raised me."

JUST WATCHED Ivanka Trump's entire speech introducing Donald Trump Replay More Videos ... MUST WATCH Ivanka Trump's entire speech introducing Donald Trump 15:39

She was by her father's side this week when he unveiled a child care policy crafted with Rep. Cathy McMorris Rodgers, R-Washington, that guarantees six weeks of leave for new mothers.

When Cosmopolitan magazine's Prachi Gupta grilled Ivanka Trump on what that policy meant for gay couples -- asking if after an adoption, "they would not be receiving special leave for that because they don't need to recover or anything" -- the interview turned contentious.

"So I think that you have a lot of negativity in these questions, and I think my father has put forth a very comprehensive and really revolutionary plan to deal with a lot of issues. So I don't know how useful it is to spend too much time with you on this if you're going to make a comment like that," she said.

When pressed on how Trump would pay for his proposals, including increased defense spending an a US-Mexico border wall, Ivanka Trump cut off the interview. "I'm going to jump off, I have to run. I apologize," she said.

She followed up with a series of tweets Thursday encouraging Cosmopolitan to "keep the focus where it belongs -- advocating change."

Trump Jr., meanwhile, stepped into several controversies in interviews conducted Wednesday.

He attacked New York Attorney General Eric Schneiderman for failing to investigate the Clinton Foundation, "which has decades of pay-to-play -- of meetings through the State Department."

But when asked about The Donald J. Trump Foundation -- his father's charitable organization, for which Trump Jr. is a director -- paying for a portrait of Trump, he denied knowledge as a campaign aide ended the interview.

"No, I don't know anything about that," Trump Jr. said.

As reporter Bob Mayo asked "how come you didn't know," an off-camera voice interrupted to say: "Alright, that's it. We have to move on to the next one. Thank you."

Trump Jr.'s "gas chamber" remark was the most provocative.

It came as he complained about how the treatment his father has received by the political press compares to coverage of Clinton.

"The media has been her number one surrogate in this. Without the media, this wouldn't even be a contest. But the media has built her up. They've let he slide on every indiscrepancy, on every lie, on every DNC game trying to get Bernie Sanders out of the thing," Trump Jr. told Philadelphia-based conservative talk radio host Chris Stigall on Wednesday.

Trump Jr. added: "I mean, if Republicans were doing that, they'd be warming up the gas chamber right now.

Gas chambers were used by Nazis in the Holocaust -- the genocide of 6 million Jews and millions of others during World War II.

Trump's campaign denied that Trump Jr. was referring to the Holocaust, saying he meant the "gas chamber" used in capital punishment.

"The liberal, dishonest media is so quick to attack one of the Trumps that they never let the truth get in the way of a good smear," Trump senior communications adviser Jason Miller said in an emailed statement. "Don Jr. was clearly referring to capital punishment to make the case that the media continues to take words out of context in order to serve as the propaganda arm of the Hillary Clinton campaign -- something that's only gotten worse as Trump's poll numbers have improved."