Piers Morgan received a warning from his mum while presenting ITV breakfast show Good Morning Britain.
The 54-year-old read out the message to co-host Susanna Reid and viewers early in the shown after Mrs Morgan reminded him to be polite about the new Royal baby.
He said: "My mother texted me last night, I have got to read it, it was one of the funniest things.
"My mother camped on the Mall for Diana's wedding and Fergie's wedding, literally camped over night, that is how big a royalist she is.
"She says 'Piers, I am really worried about you knocking Meghan and Harry about this baby. Please don't, it doesn't seem appropriate.
"I'll be worrying all night about what you might say. Just think back to what you felt when your little lot were born.
"And she is quite right."
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Piers has made no secret that he is not Meghan Markle's biggest fan, but viewers of the show were impressed that there may finally be one person who can make the outspoken presenter pipe down.
One, @julienDuncan1, said on Twitter: "Ah ....... so there is one person who can make you behave !!!!!!"
ITV Good Morning Britain's Piers Morgan ignores TV bosses and takes out ear piece during live rant
Another, @JasmineJay92, said: " Not surprised his mother told him not to say anything negative cause she don’t want Piers acting like a fool by making a smart alec comment about the couple’s baby which will cause backlash, that’s a line you don’t want to cross regardless if you don’t like the couple or not."
*Good Morning Britain is one ITV1 every morning from 6am
