Former White House press secretary Sarah Sanders late Thursday mocked former Vice President Joe Biden for accentuating a stutter in his response to a question at the sixth 2020 Democratic presidential debate.

Toward the end of the debate in Los Angeles, Sanders mocked Biden on Twitter by caricaturing the stutter he used in responding to a question about whether, in the spirit of the holidays, there was a candidate on stage whom the others would ask for forgiveness or give a gift.

"I I I I I I I I I I I I I I I hhhave absolutely no idea what Biden is talking about. #DemDebate," Sanders tweeted.

In his answer on stage, Biden said Sen. Elizabeth Warren of Massachusetts, who had just emphasized her personal contact with thousands of voters when taking selfies with them on the campaign trail, was not the only person who snapped photos with voters.

The former vice president said he's done "thousands of them," adding that people often "lay out their problems," such as telling Biden — who lost his first wife and their infant daughter in a car accident nearly 50 years ago to the day and his eldest son to brain cancer in 2015 — about how they've lost a family member or asking him whether they're going to be OK.

Biden said that he and his wife, Jill Biden, have a list of people whom they call weekly or monthly.

"I tell them I'm here. I give them my private phone number. They keep in touch with me. A little kid who says, 'I, I, I, I, I can't talk. What do I do?'" said Biden, who has spoken recently about how he's dealt with a history of stuttering.

Biden responded to Sanders in a tweet, saying: "I've worked my whole life to overcome a stutter. And it's my great honor to mentor kids who have experienced the same. It's called empathy. Look it up."

I’ve worked my whole life to overcome a stutter. And it’s my great honor to mentor kids who have experienced the same. It’s called empathy. Look it up. https://t.co/0kd0UJr9Rs — Joe Biden (@JoeBiden) December 20, 2019

Sanders issued a followup tweet about 10 minutes after her initial one — both of which she later deleted — that said: "To be clear was not trying to make fun of anyone with a speech impediment. Simply pointing out I can't follow much of anything Biden is talking about."

Shortly after that, she apologized.

I actually didn’t know that about you and that is commendable. I apologize and should have made my point respectfully. https://t.co/fbmVAqDoWI — Sarah Huckabee Sanders (@SarahHuckabee) December 20, 2019

Sanders resigned as White House press secretary in June.

Sanders, the daughter of Republican former Arkansas Gov. Mike Huckabee, hinted in November that she was exploring running for governor herself.

"There are two types of people who run for office," she told The New York Times. "People that are called and people that just want to be a senator or governor. I feel like I've been called."

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Sanders' former boss has mocked people with disabilities. At a presidential campaign rally in 2015, Trump famously mocked Times reporter Serge Kovaleski, who has a chronic condition called arthrogryposis, which affects the movement of his arms, by waving his arms around in a jerky manner.