Joe Biden's brother shared an ominous-sounding comment about the president's health just hours after he announced the end of his re-election campaign.

In comments to the press, Frank Biden said his brother's decision boiled down to his "overall health" as speculation swirls about the events that led to Sunday afternoon's historic news.

Frank Biden made allusions to his brother's mortality that some might interpret as ominous.

"Selfishly, I will have him back to enjoy whatever time we have left," Frank Biden told CBS.

Biden's brother speaks

Strangely enough, Americans learned of Joe Biden's decision from a letter posted online instead of a public speech.

Biden's own staff found out only moments before his statement went public on X, formerly known as Twitter.

"It has been the greatest honor of my life to serve as your President," Biden said. "And while it has been my intention to seek reelection, I believe it is the best interest of my party and the country for me to stand down and focus solely on fulfilling my duties as President for the remainder of my term."

Biden's statement made no acknowledgment of the elephant in the room: Biden's declining cognitive health, which was exposed in front of the world in a disastrous debate with Donald Trump on June 27.

"It really boils down to this: it has to do with his overall health and vitality," Frank Biden told ABC News. "Not anything cognitive. But he's a proud guy, it pisses him off that he shuffles when he walks."

Biden family denies it

A Biden family source angrily contradicted Frank's assertion that health was a factor.

“Frank Biden suffers from alcoholism and hasn’t spoken to his brother in weeks. What he said...is completely untrue," the source told CBS News.

As recently as Friday, Joe Biden was publicly defying pressure from his own party to step down. But he changed his mind over the weekend after some frank conversations with his inner circle at his Delaware beach house, where he was isolated with COVID.

The story goes that Biden was finally convinced that his re-election bid against Trump was hopeless after consulting polling data.

It's obvious that Biden's declining health is ultimately the reason for his campaign imploding. But his brother's comments, and his family's sharp response, will lead many to speculate there is more to the story.