The Duke and Duchess of Cambridge have spent Sunday morning attending the Easter service at St Andrew’s Cathedral in Sydney.

The Duke and the Duchess of Cambridge are spending Easter Sunday with bibles and bilbies.

The royal couple returned to Sydney following a brief sojourn in Brisbane to attend a service at St Andrew’s Cathedral on Sunday morning.

They sat in the front row alongside Australia’s Catholic Prime Minister Tony Abbott and his wife Margie.

“We’ve come to honour the prince – the prince of peace as I call him,” The Most Reverend Dr Glenn Davies, Archbishop of Sydney, told the service.

He was referring to Jesus, of course.

But the big crowd outside only had eyes for Prince William and Kate, who wore a stunning dove-grey Alexander McQueen coat and a hat by Jane Taylor to the cathedral.

On Saturday night, the royals had been to an off-diary trip to the rugby.

A scrum of a different sort greeted them on Sunday morning, with hundreds of well-wishers gathering at St Andrew’s from very early morning.

Patricia Raymond, 74, arrived at 7am (AEST), wearing a Union Jack cap.

“I saw Charles and Diana at the same church when they were out here,” Ms Raymond told AAP.

“So it was absolutely wonderful to see the next generation – I’m a monarchist, I’ve got a whole cupboard full of royal items.”

A huge cheer greeted the royals’ arrival at about 10.30am (AEST). Union Jacks were waved. And camera phones whirred and flashed.

A little girl clutched a Kate doll, dressed in a wedding dress. “She’s beautiful, I love her,” she told reporters.

The service lasted a little over an hour.

As they left, William and Kate signed the First Fleet Bible; a King James edition that came over with the First Fleet in 1788.

It has previously been signed by the Queen, Prince Charles and Diana, among other royals.

William and Kate also signed a prayer book before stepping outside the cathedral into the bright sunshine.

The Queen is the Defender of the Faith and Supreme Governor of the Church of England, roles William will take on when he becomes king.

A small indigenous rights protest group had gathered on George Street with banners.

“Hey royals, give back what you stole. Sovereignty of tribes never ceded,” one of the banners read.

It was the same group that protested during the royals’ trip to the Sydney Opera House on Wednesday, the first day of their Australian tour.

The royal couple met number of choir boys and young people who’d helped make the service work.

“She came up to me and asked how I often we rehearse,” said choirboy Joshua Sanderson, 11.

“It’s really a dream come true because I’ve always wanted to see someone from the royal family.”

William and Kate are due to visit Taronga Zoo later on Sunday, which is day five of their Australian tour.

The couple – and perhaps baby Prince George – will see a bird display and then visit the bilby enclosure.

Taronga has named a bilby in the enclosure after baby George.

The couple travel to Canberra later in the night, with no official engagements planned for Monday.

On the sixth day they will rest.