Prince Harry Speaks Movingly About Princess Diana at Charity Polo Match in Florida

Harry is in Florida for the launch of his Invictus Games.

— -- Prince Harry touched down in the United States Wednesday and wasted no time showing why he's known as the "Prince of Hearts," raising money for his Sentebale charity in a charity polo match in Wellington, Florida.

"Incidentally, I found out just today that forget me nots were my mother's favorite flowers when she was growing up," Prince Harry, 31, revealed to the crowd in Wellington Wednesday.

Prince Harry's first visit to Lesotho soon after his mother's 1997 death was a life-changing experience for a younger Prince Harry.

"I was struck by the many children I met whose lives had been torn apart by the loss of one or both parents to AIDs-related illnesses," Harry said. "Having lost my own mother seven years before, I felt a profound connection to these children. In spite of the obvious differences in our lives, we shared the loss of a parent and that ever-present emptiness that could never be filled"

Prince Harry said he vowed at that moment to do something and honor his mother, who was also a passionate advocate for those suffering from AIDs at a time when no one understood the disease.

The fifth-in-line to the British throne took Florida, the Sunshine State, by storm, literally, on Wednesday. Huge electrical storms deluged the polo grounds where Prince Harry and the best polo players in the world participated in the Royal Salute Sentebale Polo Cup.

It was touch-and-go whether the flooded grounds would be safe enough to play the charity match but His Royal Highness was undeterred by the weather, joking upon his arrival by saying, "Welcome to the Sunshine State."

Harry's only concern was that the children of Lesotho not be forgotten.

Prince Harry and Sentebale ambassador Nacho Figueras, a world-class Argentinian polo player, faced off on opposing teams in what has become a tradition after seven years.

Figueras, who took the Polo Cup victory last year, remarked that Harry might have an advantage this year because of the weather.

"Harry and I have been texting each about who's going to win for days," Figueras said in Wellington. "The weather is not perfect today so whoever is better in rain, probably him. He's English. He's used to it."

In the end, it was Prince Harry's year for the win.

Win, lose or draw, Figueras and Harry's priority was raising funds to carry on the work of Sentebale. Harry announced the charity would be expanding its base from Lesotho to Botswana.

"Lesotho has the second-highest rate of HIV in the world and UNAIDS estimates that only 30 percent of adolescents living with HIV in the country are accessing medication," Prince Harry told guests after the polo match.

"Across the region, the picture is equally concerning," the prince continued. "Eighty-two percent of adolescents living with HIV are in sub-Saharan Africa, which is a staggering figure, when you consider that only 16 percent of the world's adolescents live in the region.

"It is no surprise that HIV remains the number one cause of death amongst adolescents in Africa," Harry said.

Prince Harry heads to Orlando next for his Invictus Games, which take place May 8-12 at ESPN's Wide world of Sports Complex at Walt Disney World.

Tune into "Good Morning America" Monday,from 7 to 9 a.m. ET, to watch a one-on-one interview with Prince Harry and U.S. first lady Michelle Obama at The Invictus Games.

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