The Keeping Up With The Kardashians star is due to give birth to her second child next month and looked ready to drop.
Mason looks set to be a little heartbreaker already, and grinned broadly as he held the hand of his playdate tightly.
Kourtney Kardashian and Mason enjoy a day out at the Calabasas Commons in California where they had lunch with a friend and her daughter
Dressed in a sharp outfit combo of rolled up chinos, white T-shirt and side swept hair cut, Mason is on track to become a proper ladies man as he gets older.
Standing tall: Mason perches on a wall as Kourtney points out something in the distance
Puppy love: Mason points out something interesting to his female companion
The 33-year-old opted for a summery white sleeveless dress, with delicate embroidery at the neck.
She scooped her hair into a bun and completed the look with silver drop earrings and large shades.
You looking at me? Mason pulls a face as Kourtney waves to her friend