‘Big  Bang Theory’ star Kaley Cuoco broke down sobbing when her boyfriend Karl Cook presented her with an engagement ring for her birthday yesterday (Thursday).

Cook, a professional equestrian posted the tearful moment on Instagram.

“Well after nearly two years I finally got up the courage to ask her to marry me. This is the best night of my life and I think the video shows it is the best night for Kaley as well.”

Kaley was previously married to tennis player Ryan Sweeting that ended  bitterly after 21 months.

https://www.instagram.com/p/BcJNCQAArHb/

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