Kate MiddletonandPrince William’s oldest children are paying tribute to their late great-grandfather.

Prince George, 8, andPrincess Charlotte, 6, made a surprise appearance atPrince Philip’s memorial service on Tuesday.

The siblings — who are on their Easter break from school — arrived at Westminster Abbey with their parents shortly before the start of the service.

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Tuesday’s service also marks the first public outing for William and Kate since they returned from theirroyal tour of the Caribbeanon Sunday.

Prince George and Prince William.Tim Rooke/Shutterstock

Prince George of Cambridge and Prince William, Duke of Cambridge

The poignant ceremony will provide an opportunity for representatives of the many charities and organizations thatPrince Philipworked with to pay tribute to him.Prince Philip’s funeral last April was scaled down due to COVID-19 government restrictions at the time.

Princess Charlotte and Kate Middleton.Samir Hussein/WireImage

The Duchess of Cambridge and Princess Charlotte

The royal couple returned home from their eight-day Caribbean tour on Sunday morning. Last week, William and Kate traveled to Belize, Jamaica and The Bahamas.

Just hours before their flight home,William released an unprecedented statementabout the controversy that has followed the couple on their tour.

PA Images / Alamy Stock Photo

Service of Thanksgiving for the life of the Duke of Edinburgh

For the first time, the royal couple facedsignificant backlashon an official tour. Although they have receivedwarm welcomes from many locals, they are also encountering mounting tensions in the Caribbean nations where William’s grandmother,Queen Elizabeth, remains head of state.

William reflected on the future governance of the Caribbean nations in his statement on Saturday, saying, “I know that this tour has brought into even sharper focus questions about the past and the future. In Belize, Jamaica and The Bahamas, that future is for the people to decide upon.”

Princess Charlotte and Kate Middleton.RICHARD POHLE/POOL/AFP via Getty Images

Service of Thanksgiving for Britain’s Prince Philip, Duke of Edinburgh

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Prince George and Princess Charlotte.Samir Hussein/WireImage

Prince Philip Memorial

The rising tide of social and economic justice movements — including calls for slavery reparations and indigenous rights expansion — are rapidly reshaping contemporary views of the monarchy at a time when it is in transition: As Elizabeth, 95, marks 70 years on the throne, William and Kate are increasingly the modern face of both the family and the institution.

“The future of the British monarchy is more about William and Kate—spiritually, not in terms of actual succession,” historian Sarah Gristwood tells PEOPLE.

source: people.com