R&B star Rihanna has appealed to fans to help raise funds to cover the costs of a life-saving transplant operation for a baby girl battling a devastating genetic disorder.

The Stay hitmaker has thrown her support behind the SaveSofia.org campaign, which aims to help five-month-old Brazilian child Sofia get the treatment she desperately needs after being diagnosed with Berdon syndrome at birth.

The tot requires stomach, bladder and intestinal transplants in order to survive and her parents have set a goal of $1 million (£625,000) to pay for a specialised two-year treatment programme at the Jackson Memorial Hospital in Miami, Florida.

Spreading the word about the fundraising bid on Twitter.com, Rihanna writes, "Please Help beautiful baby Sofia's family raise money in Brazil for a life-saving transplant!"