The Queen has praised Prince Charles as a dedicated and respected heir to the throne to stand comparison with any in history.
She rarely makes public comments about her children but she used a black-tie dinner staged for his 70th birthday to praise him as his own man, passionate and creative.
She added he was a wonderful father.
Her words were a ringing endorsement of the future king, who has spent a lifetime in preparation for his role as monarch.
Close family and friends from across the globe gathered in Buckingham Palaces ballroom for the glittering event including the Duke and Duchess of Cambridge and the Duke and Duchess of Sussex.
Earlier, Theresa May spoke of the princes service to the nation and also highlighted the important role he played in bringing up his sons after their mother had died at a young age.
The Queen said in her toast to Charles: Over his 70 years, Philip and I have seen Charles become a champion of conservation and the arts, a great charitable leader – a dedicated and respected heir to the throne to stand comparison with any in history – and a wonderful father.
Most of all, sustained by his wife Camilla, he is his own man, passionate and creative.
The monarch ended by comparing her son to the Duchy Originals brand of produce he founded.
So this toast is to wish a happy birthday to my son, in every respect a Duchy original, the Queen said.
During a day of tributes to the prince, Theresa May opened a Commons debate to mark the royal birthday and said the heir to the throne had spent his life defying expectations and refusing to be categorised.
Mrs May said Charles was often seen to be a man ahead of his time, citing his warnings on pollution, sustainable agriculture and the dehumanising effects of technology in the workplace.
When the prince arrived for the celebration at Spencer House with Camilla for the event he was asked by the waiting press how he felt.
He replied: How am I feeling? Older, older.
Im not sure, its rather like indigestion, many happy returns are not quite the same thing as you get older.