She has an incredible hat collection, and we can't wait to see what colour Queen Elizabeth II chooses to wear to her 90th birthday celebrations on Thursday. Bets are currently being taken, with purple the current favourite hue.
But blue is a close runner-up, with pink leading just behind. Jessica Bridge, of Ladbrokes, said: "All fingers are pointing at a purple hat, but blue is also proving to be a popular bet at 7/2."
Jessica added: "It's unlike Her Majesty to double up on colours but we can't rule pink out completely for Thursday's celebrations."
Queen Elizabeth II turns 90 on Thursday - and it's thought she'll wear purple
Other variations in the running include yellow, cream, green and gold – and there's even a slight possibility Prince George's gan-gan will pay tribute to her kingdom in the Union Jack colours.
As people up and down the country prepare to celebrate with their longest-serving monarch, Her Majesty is said to be excited at the prospect of being joined by thousands of people as she turns 90.
Or will she be pretty in peach?
On her birthday, the Queen will undertake two engagements in Windsor with her husband, the Duke of Edinburgh. She will meet locals and well-wishers during a tour of the town, and unveil a plaque marking The Queen's Walkway at the foot of Castle Hill.
In the evening she and Prince Philip, joined by Prince Charles and the Duchess of Cornwall, will attend a beacon lighting ceremony.
Her Majesty's celebrations will culminate on 12 June, and communities in the UK are being encouraged to throw street parties over the summer in her honour. And last month Prime Minister David Cameron announced pubs in London will be granted extended opening hours to mark the Queen's milestone.
On 10 and 11 June, pubs which usually close at 11pm will be allowed to stay open an extra two hours.
Which colour do you think Her Majesty will wear? Let us know in the comments section below.