Jennifer Garner Is ‘Heartbroken’ Over Dog’s Death, but Daughter Violet Being Home from College ‘Helped’ (Exclusive Source)

The actress "celebrated Thanksgiving as a family" with ex Ben Affleck and their three kids, a source tells PEOPLE

It was an emotional Thanksgiving for Jennifer Garner — and she was grateful to have daughter Violet Affleck by her side.

As the Yale University student, 19, returned home to Los Angeles from the East Coast for holiday break, she and her mom, 52, said an unexpected goodbye to their beloved golden retriever, Birdie, in late November.

The 13 Going on 30 star was devastated by the family dog’s sudden death at age 9, but having Violet — one of Birdie’s favorite people — around for the weekend made things much easier, a source tells PEOPLE.

Garner has been “heartbroken,” but “having Violet home from university helped,” the source says, noting that the family had a “nice Thanksgiving.”

The actress spent the holiday with ex Ben Affleck and their three children — Violet, Seraphina, 15, and Samuel, 12.

“They celebrated Thanksgiving as a family,” the insider says. “The kids love having everyone together. Jen hosted dinner at her house.”

Prior to their celebration at Garner’s home, the former couple and their three children also volunteered together at L.A. homeless shelter The Midnight Mission's annual Thanksgiving Street Fair.

Affleck, 52, a longtime supporter of the organization, and Garner (who split in 2015 after 10 years of marriage) appeared to be in good spirits at the charity event, smiling together for a photo on The Midnight Mission’s Instagram account.

“They truly enjoy giving back to their community and cherishing quality time together as a family,” a source previously told PEOPLE of the family’s outing.

Garner is currently dating CaliGroup CEO John Miller, while Affleck recently split from Jennifer Lopez.

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The Deadpool & Wolverine actress announced Birdie’s death on Wednesday, Nov. 27, and revealed that despite being ill, Birdie hung in there until Violet, his “person,” returned home from college.

“The vet told us that dogs often hang on until their person comes home from college,” Garner wrote in her Instagram tribute to the late pet. “And we believe Birdie did just that, so that we could pet her soft ears together and thank her for being the world’s best dog.”

To begin the post, which she filled with memories of the golden retriever, the actress wrote, “It is hard to know how to write this — it seems nuts, given the world, to mourn a pet, but since we have shared Birdie with all of you, it only seems fair to let you know of her passing.”

The Family Switch star went on to reveal that after Birdie, “a renowned foodie,” missed a meal on Thursday, Nov. 21, the family knew she was not feeling like herself. “We were surprised to learn that, not only was she very ill, she was at the end of her life,” she wrote.

Birdie — who “loved to be read to” and “knew just how to give people what they needed” — lived a “happy dog life and is now in the role she was born to play: angel girl,” Garner concluded the post. “It’s a gift to love and be loved by such a creature as Birdie the Doggie. 🐾🪽.”