Family rushed to be by her side as her health took a turn this week.
"The Queen's doctors are concerned for Her Majesty's health and have recommended she remain under medical supervision," Buckingham Palace said in a statement early Thursday.
"The Queen remains comfortable and at Balmoral," a spokesperson for the royal family added in the initial statement.
Prince Charles, Camilla Parker Bowles and Prince William were among the family members reportedly there with Elizabeth in her final moments.
Prince Harry also made the trip to Scotland, a spokesperson revealed.
Fears for the beloved monarch's well-being grew hours after she canceled a meeting with the Privy Council as doctors advised her to rest.
News of her death comes months after it was revealed Her Majesty contracted COVID-19 and was subsequently forced to cancel all of her previously scheduled engagements.
It is not known at this time if COVID contributed to her death.
According to Hollywood Unlocked, sources close to the Royal Family revealed the queen was found dead after having to cancel her previously planned appearance at the wedding of Vogue editor Edward Enniful.
That report was later debunked.
Queen Elizabeth's tragic passing comes in the wake of her big Platinum Jubilee celebration on June 4.
The televised event marked 70 years since her accession to the royal throne, making the queen the second longest-reigning monarch in world history behind France's King Louis XIV.
"As I look ahead with a sense of hope and optimism to the year of my Platinum Jubilee, I am reminded of how much we can be thankful for," the queen said during her Platinum Jubilee address on February 6. "These last seven decades have seen extraordinary progress socially, technologically and culturally that have benefitted us all; and I am confident that the future will offer similar opportunities to us and especially to the younger generations in the United Kingdom and throughout the Commonwealth."