Kaley Cuoco celebrates her 30th birthday with her sister

Happy birthday Kaley Cuoco!

The "Big Bang Theory" actress turned 30 on Monday but celebrated her birthday early with a trip to Mexico. The well-known animal lover visited Black Jaguar-White Tiger founder Eduardo Serio at his wildlife sanctuary, bringing along her younger sister, Briana Cuoco, who turned 27 on Sunday.

"2 planes, 12 best friends, one 30th bday, destination unknown = priceless," Kaley Instagrammed on Saturday along with an adorable picture of her sporting a birthday hat.

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