Johnny Depp's beloved mother, Betty Sue Palmer, died earlier this week.
Palmer died in the morning on Friday, May 20, in Los Angeles after a long illness, according to ET. She was 81.
Palmer's death came days before Depp's wife, Amber Heard, filed for divorce after 15 months of marriage. The actress, who filed a divorce petition on Monday, is asking for spousal support from Depp, 52, according to documents obtained by PEOPLE.
Depp had an especially close relationship with his mother, who was a frequent guest of the actor at various Hollywood functions over the years. In 2004, Palmer accompanied her son to the Academy Awards when he was nominated for best actor for his role in Pirates of the Caribbean: The Curse of the Black Pearl.
In 2012, Palmer was reportedly admitted to the ICU at Cedars-Sinai Medical Center in Los Angeles. And in 2014, Depp was spotted taking Palmer and Heard out for New Year's Eve dinner. "It was obvious that Johnny was at dinner with his two favorite ladies," an observer at Ago Restaurant in West Hollywood told PEOPLE at the time. "He seemed very, very happy."
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Depp has been candid about how his difficult upbringing forged a close relationship with his mom. "My mother was raised in a shack, in the wilds of Appalachia, where the toilet was an outhouse," he said in a 2013 interview with Rolling Stone. "She used to say she did the same things that her mom did – and her mom certainly didn't know any better. With my kids, they're told 75 times a day that they're loved. One thing I know is they feel loved and secure and happy and needed and necessary and a part of something."
Depp has the words "Betty Sue" tattooed inside a heart on his upper left arm, and in 1995 he spent nearly $1 million on a 43-acre Kentucky farm for Palmer, according to ET.
The actor has also spoken about how his mother's lessons have influenced his own parenting. During a press conference at the Toronto International Film Festival in 2015, Depp shared his mom's advice to him on dealing with bullies.
"I come from nothing but hillbillies," he told reporters, "and my mom said to me, 'All right here's the deal, next time anybody puts their hands on you, pick up a brick and lay them out.' "
Conceding that this lesson "says a lot about a lot," in terms of his Kentucky upbringing, Depp says that he's nevertheless "taken that advice ever since" because "it worked for me."