Princess Sofia attends opening of Sweden's parliament two weeks after announcing her pregnancy

Princess Sofia has made an appearance alongside the King and Queen, and her sisters-in-law, at the opening of Sweden's parliament a fortnight after her pregnancy was announced.

The 39-year-old is expecting her fourth child, due in February next year.

The baby will become eighth-in-line to the Swedish throne.

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At the time of the announcement by Sweden's Royal House, officials said there would be no change to Princess Sofia's program of engagements.

The royal has been busy since then, attending a number of events with husband Prince Carl Philip.

The opening of Sweden's parliament (Riksdag) is attended by the royal family each year and sees the beginning of the new parliamentary year.

King Carl XVI Gustaf and Queen Silvia, and Crown Princess Victoria and Prince Daniel, travelled to the Riksdag in a horse-drawn carriage, as per tradition.

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They were then joined at parliament by Prince Carl Philip and Princess Sofia, and Princess Madeleine and Christopher O'Neill.

Princess Madeleine and O'Neill moved back to Sweden in June with their three children after living in the United States for more than a decade.

The royal family wore co-ordinating outfits of black and white, with Crown Princess Sofia choosing a dress by & Other Stories while Princess Sofia wore a polka dot frock by Andiata.

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In his speech during the ceremony King Carl told the parliamentarians: "What you decide in this chamber will affect the Swedish people for many years to come.

"My hope and conviction is that you have respectful debates, that you listen to each other, and that you make the best decisions for Sweden."

A service was held in the Stockholm Cathedral to mark the official opening and in the evening a reception took place at Sweden's Opera House, which was attended by the royal family once again.

The royals had a change of outfit, with Princess Sofia wearing a red velvet wrap dress by Andiata, while Crown Princess Victoria wore a black and white frock by Toteme. Princess Madeleine chose an outfit by Wakakuu Icons.

Last week Prince Carl Philip and Princess Sofia toured the region of Värmland in west-central Sweden, in their roles as Duke and Duchess of Värmland.

As the visit came to an end the couple thanked their hosts and also extended a special note to those who had congratulated them on Sofia's pregnancy.

"We would also like to extend our warm thanks for the well wishes we have received on the occasion of the upcoming addition to our family," the couple wrote on their Instagram page.

Prince Carl and Princess Sofia now have three sons: Prince Alexander, eight, Prince Gabriel, seven, and Prince Julian, three.

The new royal baby will be the ninth grandchild for King Carl XVI Gustaf and Queen Silvia.

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