The "Friends" actress confirmed the news in a statement Monday morning on Instagram, alongside a picture of him holding her as a baby, followed by a series of photos of them through different stages of life.
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"Sweet papa… John Anthony Aniston. You were one of the most beautiful humans I ever knew," Aniston began her caption.
"I am so grateful that you went soaring into the heavens in peace - and without pain. And on 11/11 no less! You always had perfect timing," she continued. "That number will forever hold an even greater meaning for me now."
Aniston concluded her sweet tribute expressing more love to her father: "I'll love you til the end of time. Don't forget to visit."
Jennifer's post was filled with comments of well wishes from both fans and a variety of celebrities, including Kaley Cuoco and Chelsea Handler who both left comments with red hearts.
John was an actor in his own right, most well known for his work on "Days of Our Lives" -- where he first joined the show as Eric Richards in 1970 before playing Victor Kiriakis from 1985 until his death. The latter role earned him a Daytime Emmy Award nomination for Outstanding Supporting Actor in a Drama Series, and he was also the recipient of the 2017 Daytime Emmy Lifetime Achievement Award.
Aniston also appeared on episodes of "Mad Men," "Gilmore Girls" and "Cold Case."
"Days" shared its own tribute to Twitter, writing: "Our hearts are broken over the loss of our beloved family member John Aniston. We love you John. Your legend will live on."