See Kaley Cuoco's Birthday Tribute to 'Big Bang Theory' Co-Star and Ex Johnny Galecki (PHOTO)

Matt Winkelmeyer/Getty Images for Entertainment Weekly

Kaley Cuoco sent love to Johnny Galecki on his 43rd birthday.

The 32-year-old actress dedicated a sweet post to Galecki, her ex-boyfriend and The Big Bang Theory co-star, on the actor's birthday Monday.

Cuoco shared a throwback photo on Instagram from her first Big Bang Theory press tour with Galecki in Rome. The pair play Penny and Leonard on the long-running CBS sitcom.

"Happy happy birthday to the best tv husband a girl could ask for!" Cuoco captioned the picture. "This pic was taken during our first press tour in Rome. I don't think we had any idea the ride we would be on! Love u Mooks!"

Cuoco also penned a post to co-star Kunal Nayyar, who has the same birthday as Galecki. The actor portrays Rajesh on The Big Bang Theory.

"Aaaand another happy birthday to my pal @kunalkarmanayyar! The only guy I know who looks perfect in every single picture he takes #zoolander," she joked. "love u kunky!!!"

Cuoco and Galecki dated in secret from 2008 to 2010. The actress went on to wed Ryan Sweeting, from whom she split in September 2015 after less than two years of marriage, and got engaged to Karl Cook in November.

"Johnny's actually one of my best friends," she said of Galecki in an interview with Watch What Happens Live in 2015. "It's been a long time, so it's great. I got lucky."

By Annie Martin

Originally published in UPI Entertainment News.