The Duke of York escorted the monarch into Westminster Abbey, while Prince George and Princess Charlotte also attended.
The Queen has rallied to join close family, friends, foreign royals and hundreds of charity workers in remembrance of her beloved husband the Duke of Edinburgh at a poignant memorial service.
Front and centre of the high profile occasion was the Duke of York, despite Andrew paying millions out of court earlier this month to settle a civil sexual assault case.
The monarch held onto Andrew’s elbow with her left hand as she moved slowly and gingerly to her place, using a walking stick in her right hand.
They entered via Poets Corner – a shorter route for the Queen’s comfort – in a small procession.
The monarch’s state limousine had arrived at Poets’ Yard entrance with Andrew sat beside her after they travelled from Windsor together.
Inside the abbey, they walked at a slow but steady pace, both looking ahead, and at the end of the aisle they separated – with Andrew giving a last glance to his mother as she turned right.
As the service began, the Prince of Wales leaned over to the Queen and spoke to her briefly.
The Queen delved into her black Launer handbag for her glasses.
Andrew, who stepped down from public life over his friendship with convicted paedophile Jeffrey Epstein, had a front row seat, sitting next to his brother the Earl of Wessex and across the aisle from his other siblings.
Among those attending were Charles, the Duchess of Cornwall, the Duke and Duchess of Cambridge, the Countess of Wessex, the Princess Royal, Princess Beatrice and Princess Eugenie.
Some 1,800 people packed the gothic church – in marked contrast to Philip’s funeral where only 30 were permitted to attend amid Covid restrictions, with the Queen sat alone, masked in mourning.
The monarch, 95, had been determined to make the appearance at the deeply personal and significant occasion on Tuesday in honour of her “strength and stay” Philip – with her attendance only confirmed the same morning.
It was the Queen’s first major official engagement outside one of her homes for nearly six months, since she travelled to Cardiff to deliver a speech at the Welsh Senedd on October 14.
The Queen listened as the Dean of Windsor paid tribute to Philip’s intellect, work ethic, sense of humour and devotion to his family.
The Right Reverend David Conner described the duke as a “remarkable man” who was committed to “a host of down-to-earth enterprises”.
He pointed out that the duke could be “abrupt”, and suggested that at times he could forget “just how intimidating he could be”.
Princess Beatrice was seen to give a small chuckle as the Dean remarked: “He could be somewhat sharp in pricking what he thought to be bubbles of pomposity or sycophancy.”
The monarch, the Duchess of Cornwall and the Princess Royal were all dressed in dark green – seen as a special tribute to Philip, whose livery colour was Edinburgh Green.
Others throughout the congregation also wore the shade, including Duke of Edinburgh Gold Award holder Doyin Sonibare, who delivered a special tribute about the effect Philip’s youth scheme had on her life.
The Queen stopped to speak to Ms Sonibare at the end of the service, smiling broadly as they chatted briefly.
The monarch was heavily involved in arrangements for the service which featured elements Philip planned for his own funeral which were forbidden due to Covid-19 restrictions.
A rousing rendition of the hymn Guide Me, O Thou Great Redeemer – also known as Bread Of Heaven – was one of his particular requests, but congregational singing was banned at the time of his death.
Eleven months on, those who knew and loved Philip sang the anthem with gusto as the song echoed around the vast church.
Other missing gestures from Philip’s pre-pandemic Forth Bridge plans saw Gold Duke of Edinburgh’s Award holders and members of the youth UK Cadet Force associations line the steps of the abbey, and prayers being said by the clergy from Windsor, Sandringham and Balmoral.
Special arrangements were put in place for the Queen’s comfort, with the service limited to 40 minutes and the monarch sitting in one of the Canada chairs but with an additional cushion.
The difficulty for the Queen, who has confessed to not being able to move, was understood to be whether the monarch would be able to walk to her seat.