Kaley Cuoco announced yesterday (Dec. 31) that sadly, her first dog Petey has passed away.

In an Instagram post featuring past photos of her and Petey, The Big Band Theory star writes:

"Anyone who knows me, knows Petey. He was basically the first dog I ever had... I was gifted him on my sweet 16, by my bf at the time.. I was afraid I would get in trouble so I hid him in my bedroom for 3 days until my parents found out- they said I had to take care of him if I was to keep him , that he would be mine! I was so excited!! When I moved out of my parents house at 17, I had plans to take him with me but he had stolen my parents hearts and they wouldn't let me! Here we are 15 years later. My folks gave him the greatest life and he taught us what it meant to love an adoption pup. I have since named my corporation after him (peteypie inc) and he has brought a lifetime of joy and laughs to our entire family. I know he will now enjoy doggie heaven where there will be an abundance of greenies just for him. This little guy, I will never ever forget."

Cuoco frequently shares photos of her other dogs on Instagram, which includes Ruby, Chester, Norman and Shirley. She's an avid supporter for animal rights and pet adoptions, and frequently helps out with celebrity charity events and organizations.

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