It took a small, innocent baby to tame the wild beast known only as “Dame Heigl”. This is according to Betty Confidential’s sources, who claim that since Heigl adopted her beautiful little daughter Naleigh and brought her home from Sourth Korea, Dame Heigl has been almost professional and nice! While coworkers previously described Heigl as “unprofessional” or “diva” or “unfortunate” or “Jesus, shut up, bitch,” now Heigl is being described in glowing terms as “tolerable”. Chuckle. That one is still cracking me up. My God, her co-workers must hate her, if there’s this huge story about how Dame Heigl has changed so much and now, at long last, she’s “tolerable.”

What a difference a baby makes! That’s what stars of Grey’s Anatomy are saying about their co-worker Katherine Heigl. A source tells BettyConfidential that Katherine has become a changed woman since she and her husband, singer Josh Kelley, adopted their daughter, Naleigh, a special-needs child from South Korea last fall.

“She’s mellowed out since bringing home Naleigh,” says the source. “She’s a doting mom. She doesn’t like to be apart from her baby, so she brings her to the set as often as she can.” And co-stars are not complaining! “Katherine loves showing off Naleigh. And her co-stars get a kick out of her,” says the insider. “She’s such a good baby. She’s always smiling and hardly ever cries.”

As BettyConfidential previously reported, Katherine (who returns to TV screens tonight as Dr. Izzie Stevens) had been labeled a diva on the set. “She’s really trying hard to be pleasant and not offend anyone this year,” adds the source. “She’s by no means anyone’s best friend, but she’s tolerable and that’s the main thing. Everyone is more at ease with less tension on the set.”

When Katherine joined Grey’s Anatomy in 2005, she and her now ex co-star, TR Knight, became fast friends, but it seemed the pair courted drama. Katherine complained loudly and publicly about her long working hours and TR had a much-publicized feud with Isaiah Washington. Last season, when TR left the show, everyone thought Katherine would be easier to work with, but that wasn’t the case.

“She and TR hung out together on the set all the time. Once he was gone, everyone thought she’d be friendlier. But she started rattling the cages again, complaining about scripts.”

The cast was even relieved when she took time off last year to film her upcoming movie, Five Killers, with Ashton Kutcher. And, then took another five weeks off this season to film the romantic comedy Life As We Know It. But, now it seems that motherhood has made Katherine more laid-back and the insider says it’s interested to see the changes in everyone on set as they gather around her and her well-behaved baby.

Could it be that Katherine now has more in common with her co-stars? Ellen Pompeo had a baby last year and Chyler Leigh already brings her daughter, Anniston, to the set, and Eric Dane and his wife, Rebecca Gayheart, are expecting their first child together, a girl, later this year.

The source adds that even directors and producers have been commenting on how easygoing Katherine has been lately. But no one is analyzing it too much; they’re just happy that the drama is now contained to what’s going on in front of the cameras!

[From Betty Confidential]

I think it’s perfectly possible and probable that Katherine is toning it down, maturing, and learning how to be more professional and classy. Is it because she’s a mom now? Could be. It could also be that she finally got into her head that her big diva mouth was destroying her career. You know what I’ve noticed, though? Since adopting Naleigh, Katherine has barely talked to the media one way or the other, letting her charity do most of the talking on her behalf. She’s also been MIA for any kind of promotional duties for Grey’s Anatomy. Interesting… could it be that there’s another Dame Heigl moment coming, just waiting until she gets in front of a journalist?

Photos of Katherine, Josh and baby Naleigh courtesy of Betty Confidential and Celebitchy’s previous posts.