The 37-year-old model sends the 41-year-old reality star samples from Kora Organics to sell on her lifestyle website and loves to know what Kourtney thinks of her latest products.
Speaking to Glamour, she said: "Kourtney actually loves Kora and she sells it on her Poosh site as well so it's great to have her support. We just sent out all the milky mushroom boxes, so I have to check in with her to make sure she's received it because I’d love to get her feedback obviously."
The two pals have become even more committed to clean living since becoming mothers because they want to set a good example to their children and have since exchanged tips and products.
Miranda added: "She is very much into health and wellness which is great and she gave me one of those LED masks and I've used it a couple of times."
Miranda has three children, 10-year-old son Flynn, from her marriage to Orlando Bloom, and two sons, Hart, two, and 10-month-old Myles, with her husband Evan Spiegel.
Kourtney has three kids, Mason, 11, Penelope, eight, and Reign, six, with her former partner Scott Disick.
Meanwhile, Miranda has adapted saying a positive affirmation into her morning ritual after reading how it can help put a "positive spin" of her mood.
She explained: "I was reading this book called 'Tiny Habits' by BJ Fogg and he talks about when you wake up in the morning, just say today's going to be an awesome day, and that's a little habit I've been doing that really helps put a positive spin on things."
The former Victoria's Secret Angel also likes to soak up the "energy from the sun" in the morning to give her body a boost.
She continued: "Another thing I like to do is go outside and open my hands towards the sun and just feel that energy from the sun filling my whole body with light and visualise every cell being renewed with the beautiful loving energy of sunshine."
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