Kaley Cuoco and Henry Cavill were romantically linked for a brief time back in July 2013

Kaley Cuoco's lips are sealed!

During an appearance on Tuesday night's episode of Watch What Happens Live, the 35-year-old actress — who briefly dated onscreen Superman Henry Cavill back in 2013 — was asked to respond to fan question about whether "the Man of Steel" is "really made of steel."

"Oh my God," she replied, laughing heartily before replying, "I don't know. I never say, 'I don't know' — I always have an answer — but I don't know."

Cuoco and Cavill, 37, were romantically linked for a brief time back in July 2013. PEOPLE confirmed just 12 days later that the two had called it quits.

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Kaley Cuoco and Henry Cavill go shopping hand-in-hand at Gelsons in Sherman Oaks, CA
Kaley Cuoco and Henry Cavill
| Credit: Splash News
kaley cuoco
Kaley Cuoco

Cuoco tied the knot with Karl Cook on June 30, 2018, in a ceremony at a horse stable near San Diego, California, attended by close friends and family. The duo started dating in spring 2016 and made their first public appearance as a couple in September that same year.

To celebrate their two-year anniversary this past summer, the actress and the professional equestrian both posted loving tributes on their respective Instagram accounts.

"Happy 2 year anniversary my darling @mrtankcook!! How did I get so lucky?" began Cuoco, who shared multiple photos from their intimate nuptials, in her post. "You are the coolest, weirdest, funniest, smartest, kindest, calmest, silliest, veggie growing, bunny wrangling, doggie rescuing, horse loving, beer/bourbon connoisseur, who loves and supports every move I make. I LOVE YOU and I LOVE US!!!!! ❤️❤️❤️❤️❤️."

At the end of November, the couple shared the sad news that their dog Petunia had died.

"After a life of untold loneliness and hardship, she is at rest. For that, I am happy," Cook, 29, wrote in a touching post dedicated to their pup, who they adopted when she was already a senior. "We did what we [could], adopted Petunia to do better than anyone else, give her everything."

"She is resting at peace, with everyday's sunset to warm her. That is what matters most," Cook continued. "Petunia, it is not the amount of time together, but it's [the] affects on the soul. You affected everyone who met you."

Cuoco also memorialized her dog on her Instagram Stories, making sure to give a shoutout to Paws For Life K9 Rescue, the nonprofit that initially rescued Petunia and where they adopted her from.

"We were so honored to love her in her final days," Cuoco wrote. "We love you dear special Petunia. You are the reason we continue to save dogs just like you. And we will never stop."