The former England rugby captain is open about his royal life and this includes giving casual interviews to the press.
A source told the Mirror: “Mike is adored by all members of the Royal Family for his down-to-earth nature and good humour.
"He doesn’t take himself too seriously and there’s not a snobby bone in his body.
“But recently it’s been felt he may inadvertently reveal something that should remain private.
The warning is said to have come after the father-of-two said little Mia and Lena hadn’t met their cousin Archie Harrison yet.
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