Kaley Cuoco and Johnny Galecki dated on-and-off screen and "The Big Bang Theory" season 9 will start with a wedding between Penny and Leonard. Does her husband Ryan Sweeting have any reason to worry? 

The 29-year-old actress said that she's very lucky to have a supportive husband and an ex-boyfriend who are both getting along so well.

Interviewed on "Watch What Happens Live," Kaley Cuoco said that she dated Johnny Galecki five years ago and they both moved on from that romance. The actress also spilled details on her husband's relationship with her ex.

"Johnny is actually one of my best friends - it is a situation that ended well I understand that sometimes it doesn't," she said.

"Ryan loves him, Johnny loves him," she added, referring to her husband's relationship with her former boyfriend. 

Speaking about Johnny Galecki, she added, "He is one of my best friends."

Meanwhile, Kaley Cuoco posted on Instagram a photo of her character Penny's wedding to ex-boyfriend Johnny Galecki's character Leonard on "The Big Bang Theory."

"We're back baby!!!" she wrote. "Don't forget to tune into @bigbangtheory_cbs tonight- I mean it when I say, I've waited for this moment since the pilot ... nine years in the making!!"

Some of the fans actually called the actress out for dishing spoilers for the season 9 of the ABC series as they still didn't know that Penny and Leonard's wedding.

But Steve Molaro told TVLine that Penny and Leonard being married should be a good start to "The Big Bang Theory" season 9.

"We're nine years in and we want to keep things moving forward, as well as exciting and scary and fun," he said. "And I think this a great way to do it. Penny has had commitment issues for years and years now, especially when it comes to Leonard, and even she feels, 'How much longer are we going to go back and forth on this? Let's just jump in and hope for the best.'"

Just early this year, Kaley Cuoco and husband Ryan Sweeting have been hounded by divorce rumors and the pair proved the talks wrong.