Jennifer Garner Talks Thanksgiving Plans at Baby2Baby Event, Attends Church With Ben Affleck Next Morning

Jennifer Garner partied with pals at the annual Baby2Baby Gala presented by John Paul Mitchell Systems in Culver City, California on Saturday, where she was honored with the charity's Giving Tree Award for her dedication to children in need around the world -- before spending a quiet Sunday at church with her ex, Ben Affleck, and their three children.

Before she accepted the award on Saturday however, ET's Cameron Mathieson caught up with Garner on the red carpet, where she dished on her Thanksgiving plans this year.

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"I'm cooking!" the mother-of-three said. "I'm cooking -- always, everything!"

Garner, who wore a deep navy organza Roland Mouret gown embellished with fabric flowers to the charity fundraiser, is a passionate advocate for underprivileged children. She serves on the Board of Trustees for Save The Children -- which, as she told ET, is how she got involved with Baby2Baby -- so the award is a meaningful one.

"Everyone who tries to help kids, we're all just different pieces of the puzzle," the Miracles From Heaven star said. "But you can't help kids without food in their bellies, you can't help kids without clean bottoms, and you can't help kids without some basic bare essentials, and that's what Baby2Baby takes care of so beautifully."

The award, given every year to a mother who uses her position in the public eye to advocate on behalf of low-income children, was presented by Garner's friend and fellow actor, Matthew McConaughey.

"It means the world to me that he came all the way out here," the 44-year-old actress said. "What a good pal."

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Garner was clearly thrilled to see her pal, as she sported a huge grin while chatting with McConaughey inside the shindig. 

ET also caught up with UnReal actress Shiri Appleby, who had only glowing praise for Garner. "I think she's a really wonderful example of a woman that's able to do it all -- work, be a mother and give back. I think those are the kinds of women we are looking to highlight in life." 

Garner pals and fellow multi-hyphenates Jessica Alba and Kate Hudson were also at the gala, and the trio looked radiant posing together. Other celebs at the soiree included Dax Shepherd and wife Kristen Bell, Kelly Rowland, and Molly Sims, plus music by Boyz II Men.

On Sunday, Garner attended a much more low-key event -- church services with her ex, Ben Affleck, and their three children, daughters Violet, 10, and Seraphina, 7, and 4-year-old son, Samuel. The couple have continued to co-parent their children since announcing their separation last year, and remain on friendly terms -- they even voted together in the presidential elections last week!

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An eyewitness said the couple, who were also spotted together carrying trays of cookies, are well known at their local church. "She was smiling and talking to people. Ben was more reserved -- low-key. He kept to himself," the eyewitness said. "When everyone was greeting each other in the beginning of Mass, both of them stepped out of the pew to shake hands and say good morning with their neighbors."

“They seemed to be happy. They were there for their children,” the eyewitness added.

ET recently also caught up with Jennifer at the Save The Children Illumination Gala in New York City last month, where she talked about the importance of teaching her children to be a "citizen of the world." Find out more in the video below!

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