"ETERNALLY 12": American singer Mariah Carey may have turned 50 last Friday, but she is still young at heart.

The singer posted on Instagram a photo of herself with a birthday cake and her 8½-year-old twins standing behind her.

It was captioned: "Spent 3.27 at home with my family and virtually with fans and friends from all over the world.

Thank you for all the love." She also added the hashtag #eternally12. In a separate post, she shared that she was spending her birthday recording at her home studio, "Starting 327 with a new song #stayhome".

Carey is known for her five-octave vocal range and use of the whistle register.

She rose to fame in 1990 after releasing her eponymous debut album, which topped the Billboard 200 for 11 consecutive weeks.

Her hit singles include Hero and All I Want For Christmas Is You.