Sadly Joe Simpson was diagnosed with cancer in October.

In Touch can exclusively reveal that the father of Jessica and Ashlee Simpson is battling stage 4 prostate cancer — which has spread to his lymph nodes.

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"The grim news devastated the entire Simpson family at first. Jessica and sister Ashlee especially took it hard," says a source. "They cried for days about his dire future, and the very real possibility of him dying. But, after initial shock wore off, they rallied behind him."

joe simpson family getty images

The insider adds that doctors have yet to "put a percentage on his chances of survival."

Joe is said to maintain a "contagious upbeat attitude" while his loved ones rally around him.

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"Joe has remained incredibly optimistic about his battle — carrying on with regular chemotherapy treatments and hormone therapy," the source explains. "[His family hopes] for a miraculous recovery for Papa Joe, and they are praying with all their hearts."

A rep for Joe confirms In Touch’s exclusive information on Joe’s illness and surgery, but denies that it is Stage 4 cancer and says Joe has not undergone chemotherapy treatment.

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