Inside Dolly Parton & Kenny Rogers' Steamy Sin City Hookup

Is Dolly Parton hiding a sexy secret? Despite decades of denials, the singer and her fellow country star Kenny Rogers once ended up in the sack together, sources claim.

"Kenny and Dolly did the deed — it happened way back in the 1980s when they were working together," a Nashville insider close to both entertainers confirmed.

A second inside source added: "They've privately admitted they went to bed together. They were on top of the world at the time with their duet and No. 1 hit — 'Is- lands in the Stream.' They were performing together, and they just sort of fell into each other's arms one night. It happened in Las Vegas!"

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Rumors of an affair have dogged the two music titans for years. Rogers would add fuel to the fire by constantly flirting with Parton — and she teased him right back! Recently, they once again failed to douse the incendiary whispers.

"We never consummated anything," Kenny, 78, said. "We just teased each other all (about) it."

The 71-year-old Dolly added: "We never even flirted — not in that way."

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Rogers further fueled the innuendo, saying, "I'll guarantee you everybody thinks we did."

At the time of their alleged affair, Parton had been married to her rarely seen husband, Carl Dean, now 75, for nearly 20 years, while Rogers was married to his fourth wife, Hee Haw actress Marianne Gordon, for six years.

Parton fessed up to cheating in an 1984 interview with The National ENQUIRER. "I've had my little affairs," she said. "I've been tempted many times, and I admit I've given in more than once."

According to the Nashville insider, Parton has confessed all her dirty secrets to longtime best friend Judy Ogle.

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While Parton insist she and Ogle have never had a sexual relationship and has repeatedly denied she is a lesbian, the beloved singer admitted the two are so close they even share the same bed when they travel.

Said the insider: "If Dolly, Carl, Judy and Kenny ever got in one room together and told all — it would make the walls steam!"