Julia Roberts hosted a barbecue for her 'Wonder' co-stars to help them bond.
Julia Roberts
The 50-year-old actress - who has 12-year-old twins Hazel and Phinnaeus and 10-year-old son Henry with her husband Daniel Moder - plays the matriarch of the Pullman family opposite Owen Wilson as her husband and Jacob Tremblay and Isabella Vidovic as their children, and she felt the most important thing to make the movie a success was for them all to seem like they had a genuine familial connection, so she tried to get them all together before they started filming.
She said: "I think our biggest responsibility as the Pullman family -- Owen, myself, Jacob, and Isabella -- was to seem like we really know each other and love each other and get along and have our challenges, to have some authentic energy among the four of us.
"Owen and Bella had come over to my house in California before we all set off. We were just having a barbecue, and they hung out.
"She brought her mom, and Owen brought his son. It was just great to meet each other's families.
"Then you instantly have a kind of understanding of where a person resides in the world. That, for me, was incredibly valuable."
But Julia only got to meet 11-year-old Jacob - who plays a youngster with a facial deformity starting school for the first time - just once before they started filming, but he made an instant transformation into his character, Augie, and the actress felt very protective of him.
She added in an interview with Entertainment Weekly: "With Jacob, I only met him one time, which was the first day we were all together as a cast.
"Then after that, I was only ever with Auggie, who felt like my son. I loved him and treasured him, and I worried about him and tried to protect him. It all just seemed very true."
But the Oscar-winning actress believes that what truly brought them together was Owen's "earnest humour".
She said: "I think Owen brought an incredible earnest humour to the family, which I didn't see coming. I just thought it was the thing that really connected all of us."
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