Prince Harry has said he hopes his late mother would be "proud" of his fundraising efforts, as he launched a project to help disadvantaged children in South Africa.
The Prince mentioned Diana, Princess of Wales, as he gave a speech at a gala dinner for his Sentebale charity.
Earlier in the day, he met youngsters at a school for deaf children in Lesotho, where he learned sign language and took part in a kneeling dance.
The royal hopes to raise £2.5m to build the Mamohato Centre, which will provide psychological care and offer mentoring to children with HIV/Aids.
"It seems only right that it should be named after His Majesty (of Lesotho) and Prince Seeiso's mother, Queen Mamohato Bereng Seeiso," he said in his speech in Johannesburg.
"She was so loved as the mother of the nation. I hope she would be proud of what we are trying to achieve in her name.
"I hope that my mother will be proud, too. Maybe, just maybe, they are together somewhere up there, with blueprints and sketches already mapped out. I can only hope we put the swings in the right place."
Harry told guests that the Mamohato programme was already "transforming the lives of children living with HIV".
He said: "I have met some of the children who have attended the Mamohato Camps, and they have so much more confidence and knowledge of how to live healthy lives."
During his visit to the Kananelo Centre for the Deaf on the outskirts of Maseru, the capital of Lesotho, the Prince was seen writing on a blackboard and laughing with the children.
He joined the country's Prince Seeiso for a cookery class, making a kind of doughnut known in the local Sesotho language as makoenya.
Sky News' special correspondent Alex Crawford, in the capital, said: "He interacts incredibly beautifully with young people, even those who are deaf, when communication is obviously an issue.
"But he was learning and asking them through sign language experts what their favourite subjects were at school and they were all really straining to talk to him, obviously overwhelmed by him."
Harry also visited St Bernadette's Resource Centre for the Blind in the city, where he watched children learning Braille and joined students for a game of five-a-side football.
The Prince, who recently completed a four-and-a-half-month tour of Afghanistan, set up the Sentebale charity with Prince Seeiso in 2006 in memory of both of their mothers.
He last visited Lesotho in June 2010 when he took his brother, the Duke of Cambridge, to see the charity's work as part of their first joint overseas trip.
Lesotho is one of the most impoverished nations on the continent.
Half of the 1.8 million people who live there are under 18 and of those, 40% are classed as vulnerable or are orphans.