Sam Faiers and Billie Shepherd are devastated over the death of their grandmother Nanny Wendy.
Nanny Wendy died aged 77 after she was diagnosed with pneumonia.
Filming The Mummy Diaries has reportedly been stopped while the family grieve.
They had just started filming for the family reality series in December with some scenes focusing on Sam's 30th birthday.
Reality star sisters Sam and Billie had an incredibly close relationship with their grandmother.
Nanny Wendy often joined the glamorous reality stars on holiday and at events.
Sources shared her death has come as a "complete shock" to the family.
Nanny Wendy was the mum to their biological father Lee Faiers.
A source close to the family told MailOnline: "The girls are completely devastated.
"They were very close with their Nan and her passing has come as a complete shock to the family."
Sam and Billie have yet to speak out on social media.
The Mirror has reached out to Sam Faiers and Billie Shepherd's representatives for further comment.
Billie has been filming Dancing on Ice 2021.
She's competing on the show with her professional skater Mark Hanretty.
Sisters Sam and Billie have invited cameras into their lives for their own reality show The Mummy Diaries since 2016.
Prior to The Mummy Diaries, Sam and Billie rocketed to fame on TOWIE.
