"The nanny is with him all the time when he is with Orlando," the 31-year-old supermodel told The Sunday Times.
"Don't get me wrong, he's a great dad, it's just me being a protective mother and wanting to make sure all his needs are met. I want to keep Flynn's routine."
She claims that Orlando is happy with the arrangement for their three-year-old son as 'it's less pressure'.
Miranda says Flynn is her 'number one priority.' "I have a nanny who comes when I work, but when I get home she leaves and I switch my phone off," she says.
Miranda and Orlando split up last October (2013) after three years of marriage. They have since remained on good terms, although Orlando recently made headlines for snapping when teen bad boy Justin Beiber provoked him over his ex.
Miranda told Harper's Bazaar in June: "'We speak every day. We're really close, we're going to be family for ever and we both really do love each other.
"We have genuine love and respect. We're very connected and I feel grateful for that. We created something beautiful together and we both remind ourselves how lucky we are to have that. And, yeah, it's good. He's a great dad. I'm lucky."
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