Severus Snape will always be remembered. "Harry Potter" star Alan Rickman's journal recalls the decision to stay in the film franchise amidst personal struggles.

Actor Alan Rickman portrayed Severus Snape in the fantasy film franchise "Harry Potter". Rickman starred in the film franchise throughout its eight film installments from 2001 to 2011. Warner Bros. Pictures' "Harry Potter" films were based on the novel series by J.K. Rowling.

In August 2015, the "Harry Potter" star suffered from a minor stroke, leading to the diagnosis of pancreatic cancer. Rickman, later on, revealed that he had terminal cancer to close personal confidants and passed away on January 14, 2016, at the age of 69.

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Rickman's Health Struggles

In a journal he left behind, which contains entries 25 years worth of Rickman's life, the late actor recalls his initial desire to leave the "Harry Potter" film franchise, prior to filming the fifth film, "Harry Potter and the Order of the Phoenix".

During this time, Rickman had been forced to confront health issues in 2005. The actor was diagnosed with an aggressive form of prostate cancer and began to receive treatment, which was only known to his close confidants.

However, Rickman had solidified his decision to stay before filming the fifth film. "Finally, yes to HP 5. The sensation is neither up nor down. The argument that wins is the one that says: 'See it through. It's your story,'" he wrote in his journal.

The Reason Rickman Stayed

In the Guardian's published excerpts of Rickman's journal, the "Sense and Sensibility" actor revealed the real reason he decided to continue reprising his role as Severus Snape and attributes "Harry Potter" author J.K. Rowling as the reason when she revealed a secret to his character before finishing the series.

"I have finished reading the last 'Harry Potter' book," Rickman wrote in his journal. "Snape dies heroically, Potter describes him to his children as one of the bravest men he ever knew and calls his son Albus Severus. This was a genuine rite of passage. One small piece of information from Jo Rowling seven years ago - Snape loved Lily - gave me a cliff edge to hang on to."

Alan Rickman's journal will be published as a book titled "Madly, Deeply: The Diaries of Alan Rickman", and is set to release on October 4. 

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