Lilibet – the Queen’s family nickname – was first used when Princess Elizabeth was just a toddler and unable to pronounce her own name properly.
Her grandfather King George V would affectionately call her ‘Lilibet’ imitating her own attempts to say Elizabeth.
The sweet nickname stuck and she became Lilibet to her family from then on.
The Duke of Edinburgh also referred to his wife as Lilibet, writing to his mother in law after their wedding: “Lilibet is the only ‘thing’ in the world which is absolutely real to me.”
Harry and Meghan’s new baby daughter – the Queen’s 11th great-grandchild – will be known as Lili.
A variation on Lily, the flower is often seen to symbolise purity, commitment, rebirth and fertility.
Lili’s middle name Diana honours Harry’s later mother Diana, Princess of Wales.
It is no surprise the couple chose to pay tribute to Diana, who died in a car crash in 1997 when Harry was just 12.
Lili has been born almost a month before the princess would have celebrated her 60th birthday on July 1.
Lili’s cousin Princess Charlotte also has Diana as one of her middle names, as well as Elizabeth. She is Charlotte Elizabeth Diana.