I'm 99% sure that's the case.
You can see she loves expensive things, from watches to bags to shoes. If they weren't paying her, she wouldn't be caught dead wearing them LOL
Like, if someone can confirm it too, I believe she got a new Chanel Deauville canvas bag (the black one). The older one she had was black and white. So, Missoma jewellery wouldn't be at her level!
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Ok, so when she was still pregnant she had this one, and now in Miami she has a new one that's all black. Around 3/4k for a canvas bag. I guess Missoma pays well