Brad Pitt's mother Jane Pitt has died.

The retired school counsellor has passed away at the age of 84, People reports.

Brad's niece, Sydney, has already taken to social media to pay a glowing tribute to Jane, explaining that she "cared deeply for everyone and everything".

Alongside a series of throwback photographs, Sydney wrote: "My sweet Grammy, Jane Etta, 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.

"If you knew Grammy, you knew she had the biggest heart. She cared deeply for everyone and everything, no questions asked.

"She taught me how to paint, how to be strong, how to lead with kindness, to love Jesus through everything, and to find joy in the smallest things. She made up the silliest games just to make us laugh, and she believed in fairness, in putting others first, and doing good simply because it was the right thing to do.

"Every year before school, she gave each of us grandkids a "special day" which was a whole day to do whatever we wanted (and Papa had to go along with it… though I know he secretly loved it too). Mine usually started with banana splits for breakfast, hours of playing Trouble, a craft project obvi, riding every ride together at Silver Dollar City like the bada** she was, dinner at Olive Garden with Papa, mini golf where she'd make a V with her feet to help me aim… (and somehow still beat me) and ending the night watching Paulie until we feel asleep.

"She could keep up with all 14 of us grandkids without missing a beat. 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 (sic)"

Brad has yet to make a public comment about his mom's passing. However, he recently gave a shout-out to his mom during an appearance on the Today show.

He told anchor Savannah Guthrie: "I gotta say hi to my mom because she watches you every morning. To Jane Pitt. Love you, mom."