The past weekend was a bittersweet one for the Queen who marked an incredible 70 years on the throne.
Not only did it signal the start of her Platinum Jubilee year, it also marked the 70th anniversary of the death of her beloved father, George VI.
And today, in what will no doubt be an emotional week for Her Majesty, she will mark another sad anniversary - 20 years since the death of her younger sister Princess Margaret.
It was on February 9, 2002, that Margaret died aged 71 at King Edward VII's Hospital, London, after suffering a stroke.
In a heartbreaking statement announcing her death, the Queen talked of her "great sadness" and described Margaret as her "beloved sister".
The two sisters had an incredibly close bond with Margaret having a direct phone line to contact the Queen at Buckingham Palace.
Royal biographer Andrew Morton, who wrote the book Elizabeth and Margaret: The Intimate World of the Windsor Sisters, previously said Margaret had an "unflinching loyalty" to her sister.
He told Page Six: "Throughout their lives, Elizabeth and Margaret butted heads — the sensible, older sister matched with the mischievous, willful little sister. Yet they were united by a primal bond, a private world only they could share.
Love the royals? Sign up for the Mirror's daily newsletter to get all the latest news on the Queen, Charles, Kate, Wills, Meghan, Harry and the rest of The Firm. Click here to sign up.
"Central to that bond was Margaret’s unflinching loyalty to her sister. She was Elizabeth’s wing woman, able to say things that a queen would shy away from expressing."
Margaret's funeral was held on the 50th anniversary of her father's funeral on February 15, 2002, almost a week after her death.
There was said to be 400 mourners at the funeral - including an unwell Queen Mother who died just weeks later.
Margaret's ex-husband Lord Snowdon was in attendance, along with her close friend and former lover Roddy Llewellyn.
The Princess' grieving children Viscount Linley and Lady Sarah Chatto and their partners attended the ceremony too, along with The Queen and her family.
She was cremated in private at Slough Crematorium with none of her family in attendance, as she had wished.
Princess Margaret's ashes were placed in the tomb of her father George VI and they were joined by the remains of her mother just seven weeks later after her death aged 101.
