Hollywood megastar Brad Pitt is mourning the loss of his mother Jane Etta, who has died aged 84.

Her family confirmed she had passed away peacefully on August 5.

A spokesperson for 61-year-old Oscar-winner Pitt has not yet commented.

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Jane, a former counsellor, raised three children including Brad with her husband, William, in Springfield, Missouri.

Her grand-daughter Sydney, the daughter of Pitt’s brother Doug, shared a touching tribute on Instagram.

“My sweet Grammy,” she wrote.

“We were not ready for you to go yet but knowing you are finally free to sing, dance, and paint again makes it a tad easier.”

She described her grandmother as having “the biggest heart” and said she loved unconditionally and stayed close with all of her grandchildren.

“She could keep up with all 14 of us grandkids without missing a beat,” she said.

“There was no limit to the love she gave, and everyone who met her felt it.

“I don’t know how we move forward without her.

“But I know she’s still here in every brushstroke, every kind gesture, every hummingbird. She was love in its purest form.

“We were truly blessed to have her to love on growing up and I know she lives on through each of us.”

Just weeks before her passing, Pitt gave a rare shoutout to his mother during an appearance on The Today Show.

“To Jane Pitt — I love you, mum,” he said in June, while waving at the camera and blowing a kiss.

Although she kept a low profile, Jane supported her son at several major Hollywood events including the 2012 Oscars and the 2014 premiere of Unbroken, directed by Pitt’s ex-wife Angelina Jolie.

Pitt has six children with Jolie: Maddox, Pax, Zahara, Shiloh and twins Vivienne and Knox.