George Clooney is mourning the loss his older sister Adelia ‘Ada’ Zeidler who has passed away at the age of 65.

The star’s late sibling passed away on Friday, December 19 following a battle with cancer, per People.

Clooney confirmed his sister’s d3ath to the outlet on Saturday while calling her his ‘hero’ and reflecting on her bravery.

‘My sister, Ada, was my hero. She faced down cancer with courage and humor. I’ve never met anyone so brave. Amal and I will miss her terribly.’

Zeidler had ‘di3d peacefully’ while ‘surrounded by the people she loved’ on December 19 ‘at St. Elizabeth Healthcare’ located in the state of Kentucky, according to an official obituary.

Clooney’s sister was born on May 2, 1960 in the city of Los Angeles to mother Nina and father Nick while also being described as a ‘talented artist.’

George Clooney, 70, is mourning the loss his older sister Adelia 'Ada' Zeidler who has passed away at the age of 65; seen in November in London
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George Clooney, 70, is mourning the loss his older sister Adelia ‘Ada’ Zeidler who has passed away at the age of 65; seen in November in London

The star's late sibling passed away on Friday, December 19 following a battle with cancer, per People; Zeidler seen above in 2012 in Augusta, Kentucky
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The star’s late sibling passed away on Friday, December 19 following a battle with cancer, per People; Zeidler seen above in 2012 in Augusta, Kentucky

Zeidler had ‘shared her skills as an elementary art teacher at Augusta Independent School for several years.

‘In high school, her academic achievements qualified her to be a National Merit Scholar. Her love for reading connected her with other readers in a local book club.’

Clooney’s sister had also been ‘a member of the Augusta Art Guild and was a past grand marshal of Augusta’s Annual White Christmas Parade,’ the obit further read.

‘In addition to her parents, she leaves behind her beloved children, Nick Zeidler and Allison Zeidler Herolaga and her husband, Kenny; her brother, George Clooney and his wife, Amal; and several uncles, aunts, and cousins.’

A funeral is scheduled to take place next week on Monday, December 22 at St. Patrick Catholic Church in Maysville, Kentucky.

While Zeidler led a more private life, she previously showed her support for her brother over the years.

Back in 2014, she was seen attending Clooney’s Venice nuptials as he officially tied the knot with Amal.

Zeidler had been spotted standing inside a boat next to her famous brother as they rode along a canal in the city.

'My sister, Ada, was my hero. She faced down cancer with courage and humor. I've never met anyone so brave. Amal and I will miss her terribly,' he said in a statement to People; seen above with Ada as young children
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‘My sister, Ada, was my hero. She faced down cancer with courage and humor. I’ve never met anyone so brave. Amal and I will miss her terribly,’ he said in a statement to People; seen above with Ada as young children

Clooney's sister was born on May 2, 1960 in the city of Los Angeles to mother Nina and father Nick while also being described as a 'talented artist'
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Clooney’s sister was born on May 2, 1960 in the city of Los Angeles to mother Nina and father Nick while also being described as a ‘talented artist’

Back in 2014, she was seen attending Clooney's Venice nuptials as he officially tied the knot with Amal; Clooney and his sister seen at his 2014 wedding in Venice
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Back in 2014, she was seen attending Clooney’s Venice nuptials as he officially tied the knot with Amal; Clooney and his sister seen at his 2014 wedding in Venice

While growing up in the state of Kentucky, both Clooney and Ada had been very close and would often play games together.

‘I came home from work one day and George and our daughter and several friends were having a party in [a room of our house],’ their mother Nina had told HGTV back in 2006, per People.

‘They had taken [marshmallows], and they would lick one side of them, and throw them at each other. When I came in, there were marshmallows stuck all over the room.’

Ada had married Norman Zeidler in 1987 and the pair welcomed two children – with Clooney being their uncle. Norman – a retired army captain – had passed away in October 2004 of a heart attack.

During the nuptials, the actor had reportedly read scripture while their relative and Hollywood star Rosemary Clooney sang to the newlyweds.

In regards to being an uncle to his sister’s children, Clooney had previously told CBS This Morning back in 2015, ‘I’ve got a niece and nephew.

‘My nephew was just made prom king. From the high school that I went to where I was not named [prom king].’

'I came home from work one day and George and our daughter and several friends were having a party in [a room of our house],' their mother Nina had told HGTV back in 2006, per People; Clooney seen with mom Nina (far left) and father Nick in 2005
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‘I came home from work one day and George and our daughter and several friends were having a party in [a room of our house],’ their mother Nina had told HGTV back in 2006, per People; Clooney seen with mom Nina (far left) and father Nick in 2005

'My nephew was just made prom king. From the high school that I went to where I was not named [prom king],' Clooney said at the time; Zeidler and her son Nick seen above
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‘My nephew was just made prom king. From the high school that I went to where I was not named [prom king],’ Clooney said at the time; Zeidler and her son Nick seen above

He further reflected on his relationship with his sister at the time and said, ‘My sister, I’m very close to.’

Clooney has previously discussed growing in a small town in Kentucky with his family.

‘All the things we see on cable news of people being unkind to one another doesn’t exist,’ he expressed in 2019, per The Tennessean.

‘They have to get along. I was really lucky to be raised in a small town like that,’ the actor added.