Former White House press secretary Sarah Huckabee Sanders poked fun at former Vice President Joe Biden’s imitation of a stuttering child during Thursday’s Democratic presidential debate, drawing a retort from the 2020 presidential hopeful.

“There is not one line I go through that I don’t have at least a half a dozen people come up to me and go, ‘can you help me?’,” said Biden during the debate regarding people who reached out to the former Vice President for help with personal problems.

"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?'".

Sanders mocked Biden’s comments shortly thereafter, tweeting "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.”

Biden responded in a tweet of his own Friday morning, saying that he had worked to overcome his own stutter, and called his debate comments a sign of “empathy”.

“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.”

Sanders initially defended her first tweet, writing back: "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."

She later deleted both of the tweets, and replaced them with an apology.

“I actually didn’t know that about you and that is commendable. I apologize and should have made my point respectfully.”