Lady GaGa has thanked Noah Cyrus for cheering her up by singing her song 'Million Reasons'.

The 31-year-old pop star was hospitalised last week with fibromyalgia and has praised the 17-year-old ''music angel'' for making her feel better with her beautiful recital when she opened for Katy Perry at her Montreal show on Tuesday (19.09.17).

Taking to Twitter, she said: ''@NoahCyrus This really cheered me up. Keep killin it lil' music angel really warmed my heart to hear you sing my song(sic)''

The 'Poker Face' singer recently revealed she suffers from the disorder characterised by muscular pain accompanied by fatigue, sleep, memory and mood issues and apologised to fans in Brazil after having to pull out of her appearance at Rock In Rio last Friday (15.09.17).

She wrote on Twitter: ''Brazil, I'm devastated that I'm not well enough 2 come to Rock In Rio. I would do anything 4 u but I have to take care of my body right now. I ask for your grace and understanding, and promise that I will come back and perform for you soon.

''I was taken to the hospital its not simply hip pain or wear & tear from tour, I'm in severe pain. I'm in good hands w/ the very best doctors (sic)''

She also shared a full statement which read: ''Lady Gaga is suffering from severe physical pain that is impacting her ability to perform. As a result, she must sadly withdraw from this Friday's Rock In Rio performance. Lady Gaga is under the care of expert medical professionals. She sends her love to all her fans in Rio and thanks them for their support and understanding.''

Gaga is seen trying to tackle her chronic pain in her upcoming documentary 'Gaga: Five Foot Two' relates to the condition, but the singer says she's been trying unsuccessfully to keep her symptoms at bay.

She posted: ''Thought ice helped #Fibromyalgia. I was wrong & making it worse. Warm/Heat is better. Electric Heated Blanket, Infrared Sauna, Epsom Baths. (sic)''