Trump adviser Stephen Miller on Sunday raised his voice at CBS host Margaret Brennan after she pressed him on the Affordable Care Act and border security.

During an interview on Face the Nation, Brennan noted that a federal court had recently struck down part of the Affordable Care Act, and she observed that the case was likely to be appealed to the U.S. Supreme Court.

"To be clear, you're predicting that when it goes to the Supreme Court, that the Supreme Court ultimately strikes it down," Brennan told Miller.

"I believe that's it," Miller insisted. "Because it's always been unconstitutional."

"Technically, this decision wasn't possible until the tax wall was put into place," Brennan reminded the Trump adviser. "Will the president instruct Republican governors to implement the law until there is replacement?"

"Obamacare was a disaster!" Miller exclaimed. "Fortunately, again, the president has taken particular action to bring down the price of insurance on the exchanges. But Obamacare never worked. For example, even on issue of preexisting conditions, American families earning $80,000 a year have to pay exorbitant out of pocket costs if they have preexisting conditions."

"Then those preexisting conditions protections are also gone," Brennan said.

"A flawed law would be off the books!" Miller shot back.

Brennan also pressed Miller on immigration.

"One very particular case here, the 7-year-old migrant girl who passed away, she is migrant from Guatemala named Jakelin Caal, died hours after passing into U.S. Territory," Brennan explained. "While she was under the protection of customs and border control. Who bears responsibility for her death?"

"Our hearts break for the tragic death of the 7-year-old girl," Miller replied, avoiding the question. "The loss of that precious life is horrifying. It is a painful reminder of the ongoing humanitarian tragedy that is illegal immigration. The misery that it spreads."

Miller eventually suggested that the girl's death was the result of "left wing" court rulings "that incentivize the most vulnerable populations to come to our country."