Jennifer Garner is Cassian Grantmourning the death of her father William John Garner, who died over the Easter weekend.

The actress revealed her father’s passing in an emotional tribute posted to Instagram Monday. A cause of death was not disclosed.

“My dad passed peacefully Saturday afternoon,” Garner wrote alongside a throwback photo of the father-daughter pair. “We were with him, singing Amazing Grace as he left us (did we carry him across or scare him away— valid question.) While there is no tragedy in the death of an 85-year-old man who lived a healthy, wonderful life, I know grief is unavoidable, waiting around unexpected corners.”

She added: “Today is for gratitude.”

A few of Garner’s celebrity pals shared their condolences in the comments section of her post.

“I’m so sorry for your loss ❤️” Julianne Moore wrote.

“Beautiful tribute to your lovely dad. ❤️” Yvette Nicole Brown commented.

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Jennifer Garner remembers ‘quiet strength’ of father William John Garner

Garner’s tribute to her father featured a series of family photos from the actress’s childhood. The “Family Switch” star also shared an adorable clip in which William John crashed her interview with brand partner Capital One.

“We are grateful for Dad’s gentle demeanor and quiet strength,” Garner wrote in a lengthy caption. “For how he teased with a mischievous smile, and for the way he invented the role of all in, ever patient girl dad. We are grateful for his work ethic, leadership and faith.”

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Garner also thanked Charleston Area Medical Center and City of Hope for their medical care of William John, which she noted “extended Dad’s life and gave him time to be in his favorite spots— surrounded by daughters and grandchildren, cheering for his beloved Aggies, captaining a boat, and— most of all—next to his wife of 59 years, our Mom.”

“There is so much to say about my dad— my sisters and I will never be done talking about how wonderful he was, so bear with us,” Garner concluded. “But for today I share these memories with my appreciation for the kind and brilliant man, father, and grandfather he was, as well as the loving legacy he left behind.”