The 27-year-old was proposed by Sweeting just days after their red carpet debut as a couple at the Emmy Awards, reported Aceshowbiz.
"It's only been three months but she knows Ryan is the one. When you know, you know," a source said.
Cuoc was quick to share her joy on as she tweeted, "Flying high, I could literally touch the sky with you." She also posted an Instagram picture with a caption that read, "A sweet celebration with my sweet soul sisters." To her new fiance, she sent a cute photo of two penguins walking side by side with a sweet "I love you" note.
Wearing a comfy grey top, loose pants and flip-flops with a big tote bag, she was getting ready to film her latest movie coincidentally titled "The Wedding Ringer".
Cuoco was linked to Sweeting earlier this summer. She was previously rumored seeing Henry Cavill.
