Peter Krause Talks Keeping Relationship With Co-Star Lauren Graham Secret

“Parenthood” stars Peter Krause and Lauren Graham were tightlipped about the fact that they were locking lips.

The co-stars, who play brother and sister on the hit NBC series, waited awhile before telling any of the other cast members or crew about their relationship.

“Nobody really knew about it for a while,” the 48-year-old said of dating Lauren, 46, on Wednesday’s Access Hollywood Live.

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They waited “maybe a year, maybe less” before telling their co-stars.

Peter explained to Billy Bush and Kit Hoover that they prefer to not put their relationship, which has been going on for four years, in the spotlight.

“It’s a private life situation, so we keep it private [and] quiet,” he said.

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And the actor, who plays Adam Braverman on the hit drama, beamed while talking about his ladylove.

“She’s pretty great,” he added.

“Parenthood” airs Thursdays at ET/PT on NBC.

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