Naomi Watts announces the death of her grandmother

Naomi Watts is mourning the death of her grandmother.

The Australian-British actress has announced that her paternal grandmother passed away on Saturday at the age of 101.

Naomi took to her Instagram Stories on Sunday to remember her beloved family member.

"Our Granny Watts made it to 101 and a half," Naomi wrote alongside a photo of her grandmother holding a telegram from King Charles. "She got her letter from the King to celebrate her century, last night she rested in peace. RIP."

The King Kong star also shared two photos from her grandmother's 100th birthday celebrations.

"Farewell granny Watts 101.5 years old!!" Naomi, 56, captioned the second slide.

The sad news comes almost three months after Naomi revealed her grandmother Nikki Roberts had died in late August at the age of 99 after suffering a "massive stroke".

"My darling Nanna has left this world but her spirit will never leave us," the Mulholland Drive actress wrote in an Instagram post at the time. "I'm truly blessed to have had the most wonderful relationship with her. She is such a huge part of who I am: her core values, her work ethic, and her mischievous humor and joy of life."

The star added that she will "never forget" Nikki's "feisty spirit" and "no-nonsense attitude".