Kate Middleton wore a jeweled tiara at her wedding, but it was a Diamond of another sort who captivated the Duchess of Cambridge in Calgary.

Diamond Marshall, a six-year-old girl battling cancer, wanted to meet a real princess after watching the royal wedding from her hospital bed. She got her wish on Thursday, thanks to the Children's Wish Foundation and an invitation from Alberta's office of the Lieutenant Governor.

Diamond, accompanied by her father Lyall and step mother Danielle, greeted Kate and Prince William, Duke of Cambridge, as they arrived in Alberta's largest city.

The Duchess of Cambridge smiled as she kneeled down to talk to the tyke, then the prince knelt down and rubbed the little girl's back as she shyly buried her face in her mother's shoulder.

Though Kate is technically a duchess, not a princess, the distinction was unimportant to Marshall, who gave the royal a bouquet of flowers, a homemade gift, and two hugs. 

Diamond wore a pink dress along with a pink headband encircling her bald head. 

Diamond was diagnosed earlier this year with Stage IV undifferentiated sarcoma and has had two life-saving emergency surgeries. She had spent nearly a month in intensive care and there are more surgeries to come.

"She was beautiful," an enthralled Diamond later told reporters, her words muffled as she tried to hide her face in her dad's chest.

"This is a big boost for her and we're very proud of her," her visibly moved father said. "It's a big win for all our family and friends, it's great."

With files from The Canadian Press