Mayim Bialik and Johnny Galecki recreate on-screen kiss from 'Blossom'
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Kaley Cuoco isn't the only "Big Bang Theory" star who has a history with Johnny Galecki.
The cast of the hit CBS show appeared altogether on Wednesday's Conan, and things got a little awkward when the host brought up Mayim Bialik's on-screen kiss with Galecki when they were both on the hit '90s sitcom, Blossom.
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The actors were just 14 when they shared their first on-screen smooch. "It might have been my first real-life kiss also," Bialik admitted.
"Do it again!" urged their Big Bang Theory co-star, Kunal Nayyar. Jim Parsons further quipped, "What kind of show is this?"
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Bialik and Galecki eventually gave in and recreated the kiss, and they've certainly improved over the past decades.
Going along with the gag, Parsons and Cuoco also attempted an on-screen lip lock.
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It's no secret that Galecki and Cuoco dated when Big Bang Theory first started, but after the actress announced her split from husband, Ryan Sweeting, a new crop of romance rumors spread about the co-stars. "So sorry to disappoint, but no home wreckers or secret flings going on here," Cuoco responded via Instagram to the reports in January. "Me and @sanctionedjohnnygalecki are just the best of buds -- Leonard and Penny will just have to suffice!"