Miley Cyrus has become good friends with Caitlyn Jenner.

The 22-year-old singer - who is an outspoken advocate for the LGBT community and recently came out as bisexual - has praised transgender reality TV star Caitlyn, 65, for being so open about her transition and telling her story on reality TV.

Miley told America's Marie Claire magazine: ''We've talked a lot about how you can never make every single person happy.

''We always laugh about people saying she transitioned to be famous. Which is crazy. Caitlyn has to tell her story, because if she doesn't, everyone else is going to tell it for her.''

In June, Miley - who is dating Victoria's Secret Angel Stella Maxwell - raised $69,000 for AIDS research when she auctioned three customised 'Vanity Fair' covers of Caitlyn.

The 'Wrecking Ball' singer was being honoured at the amfAR Inspiration Gala at Spring Studios, in New York with the Inspiration Award alongside Andy Cohen because of her work to increase the social acceptance of transgender people.

Miley used the occasion to present her bespoke 'Caitlyn Collection' bejewelled paintings for sale to raise much needed funds in the fight against the disease.

Her bedazzling artworks were inspired by Caitlyn's recent Vanity Fair cover, which announced her new identity to the world following her gender transition from ex-Olympian Bruce Jenner.

The three creations fetched a bid of $65,000 but that figure wasn't enough for Miley and she grabbed the microphone from the auctioneer and offered to clean the winning bidder's house while naked for more money.

She yelled: ''My left boob is bigger than the right - I'll show you! What about $69,000? I'll clean your house ... naked!''

Miley's offer worked and the final sale price was the figure she asked for.

The pop mega-star is a vocal supporter of the LGBT community and the 'Caitlyn Collection' is part of her Dirty Hippie line of neon-toned, bedazzled accessories and visual arts. Miley also launched an Instagram series called #InstaPride to celebrate transgender people.

The money raised from the sale of the art will be used for HIV and AIDS research.