While the gruelling 14 hour long-haul flight from Los Angeles to France would take its toll on most people, Reese, 36, showed no sign of fatigue as she laughed and joked with co-star Matthew McConaughey in front of the world's press.
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Not long now: Reese Witherspoon stepped out onto the red carpet at tonight's premiere of Mud in a dazzling blue gown that showed off her growing baby bump
Sexy mama! Pregnant Reese wasn't afraid to flash the flesh in a stunning blue gown as she posed for the world's press with Mud co-star Matthew McConaughey
She paired diamond drop earrings, a matching bracelet and her stunning wedding ring with the full length dress for full on glamour.
Glowing! Reese and co-star Matthew were in high spirits as they walked the red carpet at Cannes
At a photocall for the movie earlier in the day with co-stars Matthew McConaughey, Jacob Lofland and Tye Sheridan, the mother-of-two showed showcased her growing bump in a little black dress.
Ever obliging, when the world's photographers shouted at her to stand up so they could see her belly in all its glory as she went to sit down, Reese duly showed off her growing figure.
Hard at work: Reese poses with Mud director Jeff Nichols and co-stars Jacob Lofland, Tye Sheridan and Matthew McConaughey at the movie's premiere in Cannes
The film's writer and director Jeff Nichols hailed Witherspoon for her small role in the movie.