Imogen and Ariana were invited to the Miss You Already Pink Picnic in association with Breast Cancer Now at Manchester Square in London on Sunday (16 August).
Imogen, 32, beamed as she cradled her baby bump while posing for photos, and little Ariana was all smiles as she got in front of the cameras to pose with her mum too.
Imogen is set to welcome her new addition in November, having recently revealed she is expecting another girl.
The Big Brother star and her long-term partner Adam Horsley announced via Twitter that daughter Ariana will become a big sister.
They said at the time: "I'm soooooooooooooo happy to announce... I'm having another little princess. I can't wait to meet her in 3 months time.... a little sister for Ariana- can't wait to see them become best friends."
Just last week, Imogen told fans she was super excited to meet her new arrival as she shared a photo of her blossoming baby bump during a workout.
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