Beyonce Knowles' little sister Solange had to "stalk" Gnarls Barkley star Cee-Lo Green when she wanted him to pen her a hit for her new album - because he wouldn't take her calls.

The singer had dreamed of collaborating with the Crazy singer on her upcoming album but fears his managers didn't like the idea of him working with Beyonce's sibling.

So she cut new tracks with random producers and hunted Green down with a demo.

She says, "I had to stalk him because a lot of the producers that I wanted to work with for the record are very credible and artistic producers and I understood why they were like, 'Huh? Beyonce's little sister?'

"So I worked on it with some unknown producers and I saw him at a club one day... and I was like, `Listen to my music before you judge me.'

"He loved it and he wrote two of the songs on the record."