Rihanna has scrapped an appearance at the Rock In Rio festival in Madrid, Spain on Thursday night (05Jul12) following the death of her beloved grandmother.

Clara 'Dolly' Braithwaite lost her battle with cancer and the Umbrella hitmaker shared her grief with her Twitter.com followers over the weekend (30Jun12-01Jul12).

The star went ahead with a show in Sweden on Saturday (30Jun12), but came under fire from fans for her shambolic performance, with many taking to Twitter.com to suggest she was drunk.

Rihanna has now decided to take time off and has cancelled her set at the Rock in Rio event.

Organisers of the festival have confirmed they are trying to organise a replacement for the grieving singer.