Ben Affleck gets points for dressing up as Batman for his and Jennifer Garner’s son Samuel’s fourth birthday. The Miracles From Heaven actress, who split from the Batman v. Superman: Dawn of Justice actor in June, told Extra that her estranged husband pulled off the “best dad moment in history.”

Garner explained that Sam asked for a superhero party for his February 27 birthday, and that they more than obliged.

“We all dressed up,” Garner, 43, said. “I dressed up as a ninja, and Ben dressed up as Batman for Sam, which was the best dad moment in history. It was pretty sweet.”

The exes, who announced their split a day after their 10-year anniversary, have remained amicable for their three kids, Violet, 10, Seraphina, 7, and Samuel, 4.

Garner recently broke her silence about their divorce in a no-holds-barred Vanity Fair interview

“I didn’t marry the big fat movie star; I married him,” the Alias alum told the mag. “And I would go back and remake that decision. I ran down the beach to him, and I would again. You can’t have these three babies and so much of what we had. He’s the love of my life. What am I going to do about that? He’s the most brilliant person in any room, the most charismatic, the most generous. He’s just a complicated guy. I always say, ‘When his sun shines on you, you feel it.’ But when the sun is shining elsewhere, it’s cold. He can cast quite a shadow.”

Us Weekly exclusively revealed that 43-year-old Affleck allegedly had a romance with their former nanny, which Garner also candidly discussed in her Vanity Fair cover story.

“Let me just tell you something. We had been separated for months before I ever heard about the nanny,” she told the magazine. “She had nothing to do with our decision to divorce. She was not a part of the equation. Bad judgment? Yes. It’s not great for your kids for [a nanny] to disappear from their lives. … I have had to have conversations about the meaning of ‘scandal.'"

Miracles From Heaven hits theaters March 18.

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