The event, held at Glencairn House, had 300 people in attendance, including soccer player Brian O'Driscoll and writer Sinead Burke.
It will be Prince Harry and Meghan's first trip outside the United Kingdom since their wedding in May. They will go on to a garden party at the Glencairn House - the United Kingdom embassy in Dublin.
The newlyweds greeted the Archbishop of Canterbury, Justin Welby, ahead of the christening service and Meghan, who shot to fame as Rachel Zane in legal drama Suits, was caught on camera giggling as she greeted the man who officiated her wedding in May.
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Farage also said May's term of governance may be coming to an end, after two secretaries resigned their posts. "I think there's something important that it's capturing about this moment in Trump's presidency".
The Duchess of Sussex wore an olive green dress by Ralph Lauren.
On the accessories front, Meghan carried a black Givenchy clutch, Birks earrings, and Aquazzura shoes.
Duchess of Sussex changes into third outfit of the day for summer garden party in Dublin.
Members of the royal family gather on the balcony of Buckingham Palace, with from left, Prince Charles, Camilla the Duchess of Cornwall, Prince Andrew, Queen Elizabeth II, Meghan the Duchess of Sussex, Prince Harry, Prince William and Kate the Duchess of Cambridge, as they watch a flypast of Royal Air Force aircraft pass over Buckingham Palace.
Harry and Meghan will "meet the people of Dublin and visit organisations which are central to Irish life".