The Queen spoke of her delight at being able to attend her granddaughter Princess Beatrice's wedding as she knighted NHS fundraising hero Sir Tom Moore.
The Monarch and Prince Philip were among a small group of guests who attended the celebrations in Windsor on Friday.
The day was extra special for the Queen as Beatrice opted to wear one of her old dresses - a glamorous cream gown from the 60s - and the same tiara she wore on her own wedding day.
Just hours after the ceremony, which was held at the private All Saints Chapel away from the public, the Queen returned to Windsor Castle to carry out her first post-lockdown engagement.
She used her father's sword to knight Sir Tom, and chatted with him and his family in the gorgeous sunshine.
During their conversation, she said: "My granddaughter got married this morning both Philip and I managed to get there - very nice."
She also thanked him for his fundraising efforts, which inspired people across the UK during the toughest part of the coronavirus lockdown.
He raised a record sum of £33million by walking 100 laps of his garden with the aid of a walking frame.
The Queen said: “Thank you so much. An amazing amount of money you raised”
“A hundred is a great age.
“Anyway it’s a nice day. Best of luck to you.”
Captain Tom set out to raise £1,000, but his incredible gesture won him fans around the world and saw his fundraising efforts soar.
In honour of his incredible achievement, there was a flypast in his honour on his 100th birthday.
Captain Tom also became the oldest person to ever score a UK Number One single with his rendition of You'll Never Walk Alone, recorded with Michael Ball and the NHS Voices Of Care Choir.
And his incredible efforts saw him awarded a special Pride Of Britain award.
Captain Tom said the response to his charitable efforts had been "outstanding".
He said: "It's hard to describe there's been so much kindness shown and so many people making kind remarks.
"It really is outstanding, I never anticipated in my life anything like this. It really is amazing.
"I really must say to everyone thank you very much to everyone wherever you are."
Beatrice married Edoardo Mapelli Mozzi at All Saints Chapel on Friday after their original wedding had to be cancelled due to the coronavirus lockdown.
They released two photos from their special day, but the bride's father Andrew did not feature in either.
