Prince Harry officially opened this year's London Marathon expo on Wednesday (Apr. 19), and he did so with a little help from a five-year-old girl. The sighting marks the royal's first public appearance since he admitted he almost had a breakdown following the death of his mother, the Princess of Wales.

Prince Harry officially opened the London Marathon expo at the ExCel on Wednesday

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The British royal picked Melissa Howse to help him cut the ribbon. Her father Tony Howse told reporters: "I don't think she knew who he was, but she was very, very excited." Prince Harry, who is Patron of the London Marathon Charitable Trust, even handed out special Heads Together headbands. The mental health campaign, which he leads with The Duke and Duchess of Cambridge, has been named this year's charity of the year for the marathon. The royals are hoping that 2017's event will be recognized as "the mental health marathon" that gets the country talking about the issue.

The British royal picked Melissa Howse to help him cut the ribbon

Kate meets London Marathon participants at Kensington Palace

In a statement, William, Kate and Harry said: "Since we launched Heads Together last May, we have seen time and time again that shattering stigma on mental health starts with simple conversations. When you realize that mental health problems affect your friends, neighbours, children and spouses, the walls of judgement and prejudice around these issues begin to fall. And we all know that you cannot resolve a mental health issue by staying silent." The royals added: "Attitudes to mental health are at a tipping point. We hope these films show people how simple conversations can change the direction of an entire life. Please share them with your friends and families and join us in a national conversation on mental health in the weeks ahead."