She will also become the longest-serving British monarch of all time in September
As she waits to welcome her fifth great-grandchild, Queen Elizabeth has notched another milestone.
The British monarch turned 89 on Tuesday, and begins a landmark year leading up to her 90th birthday.
She is said by aides to be "spending it privately" at home at Windsor Castle, about 30 miles west of London.
The Queen tends to always have her birthday at the castle with husband Prince Philip, 93, and she may be seen out horse riding there Tuesday. Members of her family may also pop in to see her and share some birthday cake, palace insiders say.
But the Queen, and the nation, will mark her birthday in more celebratory fashion in June, when the Trooping the Colour event – a ceremonial military exercise – takes place in central London
Time