Baby joy for Diana Ross' daughter

Soul superstar Diana Ross is set to become a grandmother again - her youngest daughter is pregnant with her first child.

Chudney Ross, from The Supremes star's first marriage to music business manager Robert Silberstein, is due to give birth in September.

The 36 year old revealed the news by posting a photo online showing her standing on a beach with her baby belly bulging out of a maxi dress.

In a post on Twitter.com, she writes, "Mahalo Kauai for a fabulously relaxing, sun and fun filled few days to celebrate my baby with my baby... babymoon. Headed into the home stretch! Third trimester, here I come! Yippee..."

She later updated her page with the message, "September baby!"

Singing superstar Ross first became a grandmother when her eldest daughter Rhonda gave birth to a son in 2009.