Washington (CNN) White House aide Kelly Sadler promised Meghan McCain she would apologize publicly for mocking her father's health, a source familiar with the conversation has told CNN, but Sadler has yet to do so.

Sadler, a special assistant for surrogate communications, made the promise in an apologetic phone call to McCain after it was reported that she had jokingly said of Sen. John McCain , "he's dying anyway," in response to his opposition to President Donald Trump's pick for CIA director, Gina Haspel. The Republican senator is currently at home in Arizona as he battles brain cancer after receiving a diagnosis last year.

During the phone call, McCain told Sadler she needed to apologize publicly, and the White House aide said she would, according to the source. As of Sunday, however, neither the White House nor Sadler has made a public apology.

Sadler did not immediately return a request for comment Sunday.

On Friday, Meghan McCain responded to the reports on Sadler's remarks, which she made Thursday in a private meeting, by questioning how the White House aide could still be employed.

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