The Robert F. Kennedy Jr. cheating scandal took a shocking turn as he and actress fiancée Cheryl Hines showed off matching wedding bands!

The two were photographed kissing and flashing their shiny new rings at a Fourth of July parade. While the pair was set to marry in late July at the Kennedy compound in Hyannis Port, Mass., there was speculation they may have already said “I do” in a quickie wedding.

Cheryl’s stepmom Helen Mosley told The National ENQUIRER: “No, it doesn’t surprise me if she did it that way – they’ve been together for some time now.”

Added a source, “It seems Cheryl couldn’t wait to marry Bobby and be a Kennedy. “She’s already become super tight with members of the clan, and she’s turned a blind eye to the cheating scandal.”

Also seen with the “newlyweds” at the holiday parade was Bobby’s cousin, Ted Kennedy Jr.

The ENQUIRER recently broke the bombshell that RFK Jr. – a 60-year-old environmental lawyer and notorious womanizer – had been two-timing the blonde “Curb Your Enthusiasm” beauty, 48, with a wealthy Connecticut socialite.

His brunette squeeze, 42-year-old knockout Chelsea Chapman Kirwan, is due to appear in divorce court on July 22.

According to published reports, lawyers for her estranged husband could depose Kennedy as part of the couple’s bitter custody battle.