One of President Donald Trump's biographers revealed on Sunday that the president may have a difficult time getting rid of one of his cabinet secretaries because they play an important role in his relationship with the MAGA base.

Michael Wolff, who has written four books on Trump, discussed the latest controversy surrounding Health and Human Services Secretary Robert F. Kennedy Jr. on the latest episode of The Daily Beat's podcast, "Inside Trump's Head." Wolff's comments come just a few days after Kennedy instigated the firing of the Centers for Disease Control and Prevention director over vaccine policies.

Reports about Kennedy's involvement in the CDC director's firing led some to speculate whether Trump would get rid of him.

"I think it might be problematic to get rid of him at this point," Wolff said. "Certainly, know voices inside the white House, you know, continue to be very worried about this particular issue."

Wolff added that Kennedy is an important figure in the Trump world because of his views on vaccines. Kennedy has routinely spoken out against the efficacy of vaccines, including the COVID-19 vaccine that the first Trump administration developed. Kennedy's decision to join the Trump administration gave Trump credibility with MAGA on vaccines, Wolff argued.

"They're worried that Donald Trump is weak on the anti-vax issue," Wolff continued. "So, therefore, RFK Jr. is their protection against Trump's weakness on that issue."

Watch the entire clip below or by clicking here.