Michael D'Antonio, a CNN contributor and biographer who wrote "The Truth About Trump," told CNN on Sunday that he believes President TrumpDonald John TrumpOver 100 lawmakers consistently voted against chemical safeguards: study CNN's Anderson Cooper unloads on Trump Jr. for spreading 'idiotic' conspiracy theories about him Cohn: Jamie Dimon would be 'phenomenal' president MORE was "stewing" as political leaders past and present united to honor the late Sen. John McCainJohn Sidney McCainAnother recession could hit US in 2019, says credit union association chief R-E-S-P-E-C-T: One legacy of Franklin and McCain is up to us To cure Congress, elect more former military members MORE (R-Ariz.) this weekend.

“This is a man who is really impatient when anyone else has the public’s attention,” D’Antonio told CNN's Ana Cabrera.

“He is so devoted to drawing attention to himself that he has to be restrained from tweeting when it would be against his own interests," he added. "I think that even the act of going golfing during the ceremony yesterday demonstrated who he really is.”

ADVERTISEMENT

Trump did not attend services for McCain throughout the weekend, instead visiting his golf club in Virginia on Saturday and Sunday.

Vice President Pence spoke at a memorial service at the U.S. Capitol on Friday, while White House advisers Ivanka TrumpIvana (Ivanka) Marie TrumpEx-Trump, progressive strategists battle over charges of anti-Semitism surrounding Eric Trump Ethics watchdog requests probe into Trump officials traveling to campaign events Trump praises Arizona governor's pick of Jon Kyl to succeed McCain MORE and Jared KushnerJared Corey KushnerThe Hill's Morning Report — Sponsored by United Against Nuclear Iran — Kavanaugh confirmation in sudden turmoil Manafort’s plea deal — the clear winners and losers Five takeaways from Manafort’s plea deal MORE attended Saturday's memorial at the Washington National Cathedral.

“I think it pointed up the president’s absence but in many instances, Ivanka is the person that represents humanity in place of the president,” D'Antonio said. “I think it was to his benefit she [did] so. Just as it was to his benefit that Mike PenceMichael (Mike) Richard PenceHillicon Valley: Trump signs off on sanctions for election meddlers | Russian hacker pleads guilty over botnet | Reddit bans QAnon forum | FCC delays review of T-Mobile, Sprint merger | EU approves controversial copyright law Overnight Defense: Trump marks 9/11 anniversary | Mattis says Assad 'has been warned' on chemical weapons | US identifies first remains of returned Korean war troops The Ruth Bader Ginsburg 2018 midterm elections: #Vote4RUTH MORE delivered an address on Friday.”

While Trump was not present at Saturday's memorial, multiple speakers took subtle jabs at the president, with Meghan McCain stating in her eulogy that her father's America "is already great."

John McCain, who died last week at age 81 after being diagnosed with brain cancer, was buried on Sunday at the U.S. Naval Academy in Annapolis, Md.

Trump and McCain had a fraught relationship, with the Senate icon remaining one of the president's staunchest Republican critics even after his cancer diagnosis.

Trump drew criticism when he waited nearly 48 hours after McCain's death to issue a statement expressing "respect" for the late senator.