Kaley Cuoco has announced she is expecting her second child with fiancé Tom Pelphrey.

Revealing they are preparing to welcome another daughter to their growing family, The Big Bang Theory star, 40, and Tom, 43, shared the news with followers on Instagram on Wednesday (10.06.26) through a series of family photographs featuring their daughter Matilda, three, a sonogram image and a gender-reveal cake.

Announcing the news on Instagram alongside photographs showing the family gathered around a cake with a pink centre, Tom said: "Deep gratitude and joy- so much respect and admiration for @kaleycuoco on this journey of ups and downs."

He added: "(Doc gave her a little prod for the pic and this was her immediate response…. definitely my child.)"

The actor also shared a sonogram photograph of the baby, alongside images of Kaley spending time with Matilda and a picture of the cake bearing the words "It's a…".

A large slice had been removed to reveal a bright pink filling, confirming the couple are expecting a girl.

Kaley later shared her own post celebrating the news.

She said: "Completing our little family , what a dream come true!"

Alongside photographs of her growing baby bump, Kaley added: "This second time around journey has been a little windier in many ways , but wow we are so grateful for this moment!! Little sissy on the way!!! @tommypelphrey girl dad for life and yes, the last pic is our dainty princess giving us the middle finger!"

One image showed Kaley wearing a vest top emblazoned with the words "I cried today".

The announcement comes as Kaley continues to balance family life with a successful television career, having most recently starred in the dark comedy thriller Based on a True Story.

She remains best known worldwide for her role as Penny in the long-running sitcom The Big Bang Theory, one of the most successful comedy series of modern television.

The actress welcomed Matilda with Tom in 2023 after the couple began dating in 2022.

Since then, both have frequently shared glimpses of family life on social media.

Tom is best known for his performances in Ozark and Guiding Light, while Kaley rose to international fame through her 12-season run on The Big Bang Theory.

She also earned critical acclaim for voicing Harley Quinn in the animated DC series Harley Quinn and for starring in The Flight Attendant, which received multiple Emmy nominations.

Followers quickly flooded the comments section with congratulatory messages.

One person wrote: "Yessss! I have it on good authority that all girls is the BEST! Congrats!!"

Another said: "So happy and excited for you. Best thing you can do for your child. Siblings so important"

A third added: "OMG Congratulations! Mathilda will be such a cute big sister."