Nadine Coyle wants Sarah Harding to visit as a ghost and misses her ‘all day everyday’
The Girls Aloud star paid another emotion-filled tribute to her friend, who lost her battle with cancer at the age of 39 last Sunday.
She revealed last August that she had been diagnosed with breast cancer, which had spread to other parts of her body.
The news last week shattered Nadine and all Sarah's friends.
She took to Instagram to post a series of snap of the pair smiling and posing during their years together in the pop group.
Nadine then invited her friend to come and see her as a ghost any time she fancies.
"One week without you!!" the 36-year-old captioned the pictures.
"Thinking of you all day everyday & trying to imagine how your new journey is going.
"Please feel free to come visit me anytime. I know lots of people will want some Sarah spirit time so I can wait my turn.
"I hope you now know how much you are loved & how you impacted so many lives by being wholeheartedly yourself. Always an inspiration, always a shining light & always my friend!!
Nadine was a member of Girls Aloud with Sarah, Kimberley Walsh, Cheryl and Nicola Roberts after the pop group formed on TV show Popstars: The Rivals in 2002.
Nadine said last week: "Sarah was the life and soul of the band. We laughed together, performed together, and grew together.
"Sarah was so much fun and a great friend, always. I’m truly devastated that Sarah has passed.
"She went through the last year with grace, courage, and immense bravery and I already miss her so much."
Nicola Roberts has also shared a tribute to her late Girls Aloud bandmate.
The singer, 35, took to Instagram during the early hours of Monday morning uploading some shots of herself and Sarah 'in her element'.
Captioning the three photographs, Nicola wrote: "The week has been a blur. Waves of disbelief and realisation as we navigate through this.
"Also, acknowledgment for how Sarah's passing has affected many people who are fighting this cruel disease. My heart is with you.
"Here is Sarah in her element with the artic monkey boys at the NME awards. A habitat more natural for her than any glitzy party. The most Rock & Roll in the room. Showing the indie boys how it's done. x".
Proceeds from Sarah’s last single are to be used to fund research by the cancer treatment centre that cared for her prior to her death.
Her final release, Wear It Like A Crown, topped the iTunes chart in March, with all profits going to the Christie NHS foundation, which runs the Christie hospital in Manchester where she was treated.