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Just one day after Jennifer Garner's bombshell Vanity Fair interview, Ben Affleck reunited with his estranged ex to celebrate their son Samuel's fourth birthday on Feb. 27, reports Us Weekly.

In addition to prepping for the party on Friday, Jen's candid interview also exploded all over the Internet the same day. In the revealing sit-down, the mom of three finally broke her silence on her split from her husband of over 10 years, opening up about "Nanny Gate," and referring to Ben as "the love of her life."

Despite the intimate interview going public just one day prior, the exes put on a united front for Samuel's superhero-themed birthday party, which is of course in keeping with Ben starring as Batman in the highly anticipated "Batman v. Superman: Dawn of Justice."

A source told Us Weekly that Ben attended the bash at Jen's house and there were, "lots of moms, dads and siblings." Kate Hudson's kids came with the nanny. Reese Witherspoon's son Tennessee, who was dressed as Captain America, was one of the many party goers, and so was Victor Garber, who starred with Jen on "Alias."

We were glad to see Ben made it out to the daytime event since the night before he was spotted looking somber at the William Morris Endeavor pre-Oscar bash -- and looked a bit worse for wear. The 43-year-old was at the swanky soiree with his best bud Matt Damon. Sources inside say that Ben and Matt spent a good portion of the night together.

Meanwhile, we were glad to see Jen setting the record straight in the interview about what ended "Bennifer" and it wasn't their former nanny, Christine Ouzounian. The 43-year-old actress explained, "Let me just tell you something. We had been separated for months before I ever heard about the nanny. She had nothing to do with our decision to divorce. She was not a part of the equation." The "13 Going on 30" star added, "Bad judgment? Yes. It's not great for your kids for [a nanny] to disappear from their lives." She also admitted she's "had to have conversations" with her three kids "about the meaning of 'scandal.'"

Ben and Jen may be able to be civil towards each other, but our hearts still hurt ...