"We're beyond excited and doubly blessed!" the happy couple told Us Weekly of their impending arrivals.
The 44-year-old mum-to-be played the much loved Detective Lilly Rush on the forensic police drama up until 2010 when the show ended.
Now she's swapped the crime scenes for the operating theatre, having just wrapped on a CBS drama pilot for Surgeon General. Meanwhile, 42-year-old Johnny has just finished shooting feature film The Outsider.
In a recent radio interview for the HAHAJK network, the couple gushed over their relationship. "We complement each other very well," Kathryn said, to which Johnny agreed, "I worked hard to woo her. We make the best team."
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