The sisterhood is forever! Blake Lively is supporting her Sisterhood of the Traveling Pants costar Amber Tamblyn as she prepares to be a first-time mom.

The Gossip Girl alum, 29, posted a photo in which she cradles Tamblyn’s baby bump on Thursday, October 27, just a few days after the Two and a Half Men actress announced her pregnancy with husband David Cross in an essay for Glamour magazine.

“So proud of my dear friend, and new mama to be, @amberrosetamblyn Check out her piece on @glamourmag Whatever your beliefs, one thing is certain, the world must be a better, safer place for women and girls 💜💖💜💪🏼the time is now,” Lively captioned a collage, which featured the belly-touching pic along with a throwback photo of Tamblyn and her mother.

The Joan of Arcadia actress, 33, reposted Lively’s photo, adding, “Love my Sister so much. Look at this collage she made! Someone get me a tissue!!!!!” The pair have stayed close since they played best friends in the 2005 teen drama.

In Tamblyn’s essay, she explains that after she publicly shared a story of sexual assault, she called to tell her mother the news before she read it online. “Somewhere between Donald Trump calling Hillary Clinton a woman with ‘tremendous hate in her heart’ and ‘a nasty woman,’ I found myself making a phone call to my mother I was hoping I could avoid forever,” the avid Clinton supporter wrote. “A story I shared about an encounter with an ex-boyfriend had gone viral, and I feared she would read about it in the news … Motherhood has been heavily on my mind because I am going to be a mother soon. I'm pregnant, with a daughter on the way. I think constantly about the world I am bringing her into. Will I get a phone call from my daughter someday, one she never wanted to make?”

Tamblyn and Lively may be having playdates for the kids soon. The Shallows actress and her husband, Ryan Reynolds, are parents of 22-month-old daughter James and recently welcomed their second child in September. The couple have kept quiet about the baby’s gender and name. 

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