Graham, 49, and Krause, 51, both starred on the family drama series Parenthood as sister (Sarah Braverman) and brother (Adam Braverman) from 2010-15, during which their relationship bloomed.
“We kept things pretty quiet,” Krause said about keeping their relationship hush hush at the beginning.
But before their days on the dramedy, the couple first met and worked alongside one another back in the ’90s.
“We had met on a show called Caroline in the City — a Lea Thompson show back in the day,” explained Krause. “We were guest-starring. … She had me move some furniture into her apartment for her back then. She had got some thing. I didn’t catch the signal.”
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Luckily, Krause had a second shot at hitting it off with Graham when the two worked together again on Parenthood.
“I mean, he’s really my favorite person to talk to,” she told PEOPLE about Krause. “And he always makes me laugh. He’s really, really funny.”
She added: “It’s hard to explain to people when you have a fancy job like being an actor what is challenging about it. So we just kind of have that shorthand, a shared language, which is helpful.”