Amber Tamblyn Reconnects with 'Traveling Pants' Co-Stars America Ferrera & Blake Lively at Women's Marches

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Amber Tamblyn is getting ready to welcome her baby daughter, but that didn't stop the mom-to-be from joining the hundreds of thousands of activists for two Women's Marches on Saturday.

The 33-year-old actress, who is expecting her first child with her husband, comedian David Cross, rocked a bright pink Planned Parenthood beanie to the massive protest rallies, where she reunited with two of her former Sisterhood of the Traveling Pants co-stars!

PHOTOS: Celebs Attend Women's Marches Across America

Tamblyn first hit up the march in Washington, D.C., where she met up with America Ferrera, who served as a chair for the Women's March on Washington.

Tamblyn and Ferrera posed together for a smiling snapshot commemorating the historic occasion. "Sister for life," Tamblyn wrote in the caption. "For real. Forever. #womensmarch."

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Sister for life. For real. Forever. #womensmarch

A post shared by Amber Tamblyn (@amberrosetamblyn) on

WATCH: 'Sisterhood of the Traveling Pants' Castmates Reunite With Most Adorable Pic Ever!

While in D.C., Tamblyn also caught up with her friend, comedian Amy Schumer, who came with a group of fellow protestors all decked out in bright orange NASA space suits.

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NASA's finest @amyschumer #womensmarch

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After marching in Capital City, Tamblyn made her way up to the enormous demonstration in New York City, where she joined a group of protesters who marched on Trump Tower.

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The actress reunited with Blake Lively, also of the Traveling Pants on-screen family, in the Big Apple, and the pair snapped another heartwarming selfie in front of an enormous crowd of impassioned activists.

"Sister #2 located in NYC march! #womensmarchnyc," Tamblyn wrote in the caption.

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Sister #2 located in NYC march! #womensmarchnyc

A post shared by Amber Tamblyn (@amberrosetamblyn) on

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Tamblyn, Lively, Ferrera and Schumer were among hundreds of celebrities who took to the streets on Saturday -- alongside an estimated 2.9 million other protesters worldwide -- to stand for women's rights, human rights and political freedom. Check out the video below to see how some other big-name stars contributed to the historical, multi-city rally.

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