The 24-year-old Instagram star met and interviewed the 35-year-old Girls star for her Body Protest podcast and they posed naked together on a hotel room bed – praising each other's curves and declaring themselves body "twins".
Honey Kinny shared the photo online, revealing she first saw Dunham's film Tiny Furniture she as a teenager struggling with body issues.
She said: "I wept because I’d never seen someone who looked like me – a beautiful chubby Jewish girl – be the star of the show."
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She went on: "I’m so grateful for this woman, for the stories she continues to tell. And meeting her for the first time, all these years later, proved to me that everything they say about meeting your heroes isn’t always true. She is, and will always be, a woman who holds an incredibly special place in my heart...
"We also both have identical bodies and the same specific kind of arthritis so if that ain’t special, I don’t know what is."
Dunham commented on the post: "I love you, my twin and my sister and my friend and my gal. You are a wise little bean and I’m lucky to learn from you (and to share your curvezzz)."
Honey – daughter of TV star Ross and screenwriter Jane Goldman – has previously revealed she hated her body for years.
She said: "I hated myself. I hated my body. I got such bad dysmorphia that I became convinced my friends wouldn’t be able to wrap their arms around me to hug me because I was so big."
Last year the influencer – who has 48.6k followers – accused Instagram of "hating fat bodies" after a picture of her in a bikini was removed for a "violation of community guidelines".
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