WATCH: Trump whines about 'nasty' questions as he's annihilated on air by NPR's Cokie Roberts

National Public Radio news analyst Cokie Roberts pressed GOP front runner Donald Trump about incidents of schoolyard racism and bullying inspired by his rhetoric on Wednesday morning's Morning Joe.

The real estate mogul and reality TV star-turned politician has promised to build a very large wall between the United States and Mexico, made racist comments about Mexican people, proposed banning Muslims from entering the country and has made it a habit to have black protesters thrown out of his rallies.

Trump has also been endorsed by white supremacists, which he only tepidly disavowed.

"Mr. Trump, there have been incidents of children, of white children, pointing to their darker-skinned classmates and saying, 'you'll be deported when Donald Trump is president.'" Roberts said. "There have been incidents of white kids at basketball games holding up signs to teams that have Hispanics on them saying, 'we're going to build a wall to keep you out.' Are you proud of that? Is that something that you've done in the American and social discourse that you're proud of?"

Trump said he didn't know anything about it and complained that Robert's question was a "nasty" one.

"Well I think your question's a very nasty question and I'm not proud of it because I didn't even hear of it," Trump responded. "And I certainly do not like it at all when I hear about it."

He then said Roberts was the first to tell him of it, but she pointed out the incidents had been reported widely.

Roberts then pressed Trump as to whether his racially-charged rhetoric has an effect on children, a question Trump dodged.

“We either have a country, or we don't. I talk about deporting people that are here illegally,” Trump said.

“But what about the effect on children?” Roberts shot back.

“Cokie, I also talk about building a wall and oftentimes I'll say ‘there's going to be a big beautiful door in that wall and people are going to come into our country because we want people to come in,’” Trump replied. “We want people to come into our country, but we want them to come in legally.”

“But what about the children, Mr. Trump?” a frustrated Roberts asked. “What about what the children are hearing from you and how they are responding to it?“

“Well I think people are responding very positively,” Trump said.

Watch the exchange, as posted by Morning Joe, here:

.@realDonaldTrump reacts to Cokie Roberts' question about kids using his name to taunt other kids https://t.co/1gW6cBnjiQ

— Morning Joe (@Morning_Joe) March 9, 2016