The 'Big Bang Theory' alum shares Matilda, 19 months, with her fiancé Tom Pelphrey

"When you tell her to 'cheese' and her face makes you cheese," Cuoco wrote over a photo of the trio.

In the image, the actress, wearing a light green sweatshirt, covers her mouth as she laughs, while the Ozark actor, 42, smiles widely with his arm around their daughter. Matilda sports a shirt with ruffled sleeves for the occasion, completing the look with a stuffed bunny.

Cuoco also included an adorable solo photo of her daughter grinning widely with the same stuffed animal placed next to her.

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Earlier this month, the Flight Attendant star shared that she has been struggling to get her daughter to sleep after daylight savings time turned the clocks back an hour.

Related: Kaley Cuoco and Husband Tom Pelphrey Hilariously Dress as Each Other for Family Halloween Costume with Daughter Matilda

"I finally understand what parents were always bitching about regarding their kids and daylight savings time," Cuoco wrote over a photo of herself with a large mug. "Now I know. I get it. I see you. Why is the world doing this to us?"

Related: Kaley Cuoco and Ryan Sweeting to Divorce After 21 Months of Marriage

Cuoco and Pelphrey welcomed Matilda on March 30, 2023. The couple announced her birth on Instagram at the time, calling her the "new light of our lives."

"We are overjoyed and grateful for this little miracle 💓. Thank you to the doctors, nurses, family and friends who have helped us immensely over the last few days. We are blessed beyond belief 💗 @tommypelphrey didn't think I could fall even more in love with you, but I did 💗," the actress continued in her post.

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In September, Cuoco spoke to PEOPLE in an exclusive interview about Matilda's inquisitive and fearless nature.

"She eats everything. She loves being outside. She loves her dad. She's kind of like a boy. She loves airplanes and monster trucks and helicopters. Anything in the sky she thinks is the most amazing thing," she said. "And she loves horses, so that's great."

"I used to whip her around in her carrier, in her little stroller thing when she was little, and I don't know. She's never been scared," she continued. "She thinks it's so fun."