Occasional Queen Helen Mirren donned her Queenly garb once again, although this time it wasn't for the stage or to yell at drummers -- but to make a dying little boy's wish come true.

Add this to your list of reasons why Dame Helen Mirren is the effing best.

After being diagnosed with cancer for the third time (this time, it's sadly terminal), 10-year-old Oliver Burton had but one request: to meet the Queen. Unfortunately, the actual Queen of England couldn't come through, so Mirren volunteered as a stand-in, donning her garb from the play 'The Audience' (in which she plays Queen Elizabeth) to pay the little guy a visit.

Mirren took Oliver backstage at the play to meet her corgis, and then knighted him Sir Oliver. And Burton, who also has Down's Syndrome, was convinced he had met the real thing.

“She stayed in character for the whole thing and had a butler. She was really lovely," explained Oliver's father, James of the visit.

Said Mirren to the Sun of her own experience, "It was a pleasure and a privilege to meet such a brave young man."

The meeting was arranged by the National Children’s Tumour Leukaemia Cancer Trust. Oliver, a leukemia survivor, now has a form of spine and bone marrow cancer which is not treatable.

Um, we're not crying, we just have something in our eye. While we're figuring out what it is, feel free to check out a couple more photos below.