Prince Harry has cut a ribbon to formally open this year’s London Marathon Expo at the Excel in Docklands – but he was not alone.

The royal, who is Patron of the London Marathon Charitable Trust, picked out little Mellisa Howse, aged five, to help him hold the scissors. Mellisa’s dad, Tony, will be pounding the streets of London when the Marathon takes over the capital.

Prince Harry meets a mother and her young child as he officially opens the Virgin Money London Marathon Expo at Excel

He said: “I don’t think she knew who he was, but she was very, very excited.”

Harry was making his first public appearance since admitting he sought counselling to come to terms with the death of his mother, Diana, Princess of Wales. It has been part of a concerted attempt by Harry and the Duke and Duchess of Cambridge to talk about mental health issues, promoting charity Heads Together .

Prince Harry meets runners running on behalf of his Heads Together charity

The first dozen runners in the queue for their official numbers were chosen to meet the Prince and they posed behind him as he cut the ribbon.

The Prince received widespread praise for admitting, in an interview with the Daily Telegraph, he spent nearly 20 years “not thinking” about his mother’s death and eventually got help after two years of “total chaos”.

Prince Harry helps staff and meets runners as he officially opens the Virgin Money London Marathon Expo at Excel, Docklands