While the world woke with a case of the heebie-jeebies over North Korea and its possible H-bomb, the planet was quickly and pleasantly calmed by the news from Kensington Palace that the Duke and Duchess of Cambridge — Prince William and Catherine — are expecting their third child.

The portents of such good royal baby tidings were instantly trending on social media and splashed globally. The BBC broke into its morning show to announce the news.

Monday's palace announcement, perhaps indecorously, but in keeping with the more open style of today's skinny-jeans royals, noted that the duchess, as with her previous two pregnancies, is suffering from "hyperemesis gravidarum," or severe morning sickness.

And so, the announcement continued, Catherine would not be able to carry out her planned engagement Monday at the Hornsey Road Children's Center in London.

The royal couple have already produced two children — and heirs to the throne — one son, George, and one daughter, Charlotte, ages 4 and 2, respectively.

The third child will become the fifth in line to the throne behind the 68-year-old Prince Charles, Prince William, Prince George and Princess Charlotte.

Royalist obsessives quickly noted that a third child for Prince William puts his redhead bachelor brother, Prince Harry, sixth in line for the throne.

Good news for Harry, who has observed in the past how heavy is the crown. He told Newsweek that the next generation is busy dusting off the 19th-century fusty smell from the British monarchy — and making it new again. "We are not doing this for ourselves but for the greater good of the people," Harry said. "Is there any one of the royal family who wants to be king or queen? I don't think so, but we will carry out our duties at the right time."

The Kensington Palace announcement said that Queen Elizabeth II and both families were delighted by the news.

The child will be the 91-year-old queen's sixth great-grandchild.

That the news comes as Britain paused for a bit to note the 20th anniversary of the death of Princess Diana seemed a right thing.

British Prime Minister Theresa May wished well in a tweet: "This is fantastic news. Many congratulations to the Duke and Duchess of Cambridge."

Within minutes of the pregnancy being announced, multitudes took to social media to hurrah the Duke and Duchess of Cambridge. The hashtag #RoyalBaby began trending worldwide as Twitter users began speculating about the gender of baby No. 3 and when it would arrive.

London bookies were taking bets on the possible names, with Alice and Arthur the favorites.

"Happy news for a change, love this so much," tweeted one user. Others hailed the news as the best way to start the week and banish the Monday blues.

"Another #royalbaby !! That news has made this dull Monday much better," tweeted another.

William and Catherine appeared to have had their hand forced to announce the pregnancy because of the 35-year-old duchess's morning sickness.

Jennifer Hassan in London contributed to this report.

Read more:

Princes William and Harry are all grown up, and their mother would be proud

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The power of Princess Kate and the royal family’s vulnerability

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