Jennifer Aniston News: Actress Botched Up Her Line With Julia Roberts In 'Mother's Day'

Even if they have been stars for decades, some actors are still in awe of their role models.

That happened when Jennifer Aniston was cast with Julia Roberts. In Gary Marshall's upcoming film, "Mother's Day" on Wednesday night, Aniston came up the red carpet at the premiere of the film during the famous TLC Chinese Theatre in Hollywood, Calif. She talked about co-starring Roberts and how she felt overwhelmed by the star.

"It's just a different thing when you get to work with them and then you're doing what you both do, [but] together," Aniston said. "I even flubbed in the first take and called her Julia!"

But why exactly did she feel "intimidated" by working with the Academy Award-winning actor?

"Because it's Julia Roberts! Oh my gosh," she replied.

The two had been good friends for decades. Roberts had guest starred in a Friends episode  in 1996 before they starred in "Mother's Day" together.

Aniston spelt out clearly that being just friends with a person, and working with her were two different activities.

The ironic point was made by another star-struck actor, the "Pretty Little Liars" star Shay Mitchell. At the premiere of "Mother's Day," she said that she was overwhelmed working with Aniston.

"She is so wonderful," the actress said."She truly made me feel so comfortable from the moment I got in, because I was kind of like, 'Hi?!' But you can't show that, and she was so wonderful and so amazing to work with."

While Aniston had slipped up and called Julia by her real name during one of their scenes, Mitchell said it was some ordeal for her to not call Aniston by the "Friends" name.

"I was just scared that I would say, 'Rachel!' " she joked. "The whole time I was like, 'Shh, shh.' "

You can watch the interesting chemistry between the stars in "Mother's Day" when it hits theatres on April 29, 2016.