Queen Elizabeth viewed it as a "compliment" that the Duke and Duchess of Sussex named their daughter Lilibet.
Prince Harry and his wife Meghan left many members of the royal family "bewildered" when they voiced their intention to name their second child after his grandmother's intimate nickname, but the late queen - who died in September - accepted the choice "with good grace", and was particularly approving of their chosen nickname for their daughter, who turned one in June.
Gyles Brandreth wrote in his new book 'Elizabeth: An Intimate Portrait': "According to the Sussexes, Harry sought his grandmother’s permission to use her family nickname as the Christian name for her 11th great-grandchild.
"The Queen’s recollection was a little different. According to the Queen, Harry told her the Sussexes wanted to call the baby ‘Lilibet’ in her honour and she accepted their choice with good grace, taking it as the compliment it was intended to be.
"Others in the family found the choice ‘bewildering’ and ‘rather presumptuous’, given that ‘Lilibet’ as a name had always been intimately and exclusively the Queen’s.
"Later, the Queen said: ‘I hear they’re calling her “Lili”, which is very pretty and seems just right.’ "
According to the author, the queen also gave Meghan - who also has three-year-old son Archie with Harry - her blessing to continue with her acting career after her marriage, but the former 'Suits' star assured her she wanted to be a full-time royal.
In an extract from the book published by MailOnline, Gyles wrote: "The truth is that when her grandson told her he was marrying Meghan Markle, she was truly delighted by the prospect. She liked Meghan and told lots of people so. And she did everything she could to make her future granddaughter-in-law feel welcome.
"She was concerned for her future happiness. At their first meeting, the Queen said to Meghan: 'You can carry on being an actress if you like – that's your profession, after all.'
"She would have been totally understanding if Meghan had decided to continue her career. But the former 'Suits' actress was ready for Royal duty and, of course, the Queen was delighted by that.
"She was particularly delighted by the enthusiasm Meghan showed for the Commonwealth and by the commitment she made to do 'whatever you think we should be doing for the Commonwealth'.
"Indeed, Meghan promised that when it came to the Commonwealth, she wouldn't let Her Majesty down.
"The Queen (who, of course, had seen it all before) understood that Harry's girl might find adjusting to Royal life 'challenging to begin with' (as she put it). 'It is very jolty, but you soon get used to it' – that was Her Majesty's experience going back many years."
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