Prince William and Kate Middleton
Prince William pictured with Duchess of Cambridge, Prince George and Princess Charlotte Getty

Kensington Palace has announced that the Duke and Duchess of Cambridge are expecting their third child, a new sibling for four-year-old Prince George and two-year-old Princess Charlotte due early next year.

As is to be expected, the announcement has taken over the day's news cycle and is dominating chatter on social media with thousands of people wishing the royal couple well and others making the usual jokes.

"#RoyalBaby number 3 is on the way," wrote one Twitter user. "Huge congrats to The Duke and Duchess of Cambridge." Other users described the announcement as "exciting news", while another wrote: "Three, is the magic number," quoting the famous Bob Dorough song.

Online retailer BooHoo.com expressed their congratulations with a gif of Will and Kate dancing during an overseas visit.

Moving on to the jokes, user @chiefbrody1984 posted the news with a clip from BBC News earlier this year when a reporter broke the news of June's snap General Election to Brenda from Bristol, who famously exclaimed: "You're joking... another one!?"

Other jokes referred to the new pregnancy as if it was the third film in a long-running franchise. User @samwrite used the naming convention of Ridley Scott's Alien franchise to post: "ROYAL BABY. ROYAL BABIES. ROYAL BABY³. ROYAL BABY: RESURRECTION."

Other users wanted to give the new baby a subtitle as well, including: "Royal Baby: Tokyo Drift."

Channel 4 was among those to point out that the timing of the announcement means Kate will be due to give birth around March or April, which means a stretch of paternity leave for Wills that includes the World Cup in Russia next summer.

"He's totally timed this to get two weeks paternity during the World Cup," said the channel's account. "

."

Keeping things on television, children's TV presenter/puppet Hacker T Dog posted congratulations through his account and offered a prediction. "I predict it'll be a boy," he said. "Or a girl."

User @Pandamoanimum put her pun boots on to tweet out: "Just stating now that I think 'Prince William and his three children should instead be known as 'Baldilocks and the three heirs'."

Meanwhile @rachelmcrady shared a reaction gif of Prince Harry saying it might be what he looked like when he found out about the new baby, which would bump him down the line of succession to sixth.

Comedian David Schneider got political meanwhile, tapping into a frustration among some Twitter users that the baby will be another royal taxpayers will have to pay for. In his tweet, he said "Of course, with the government's new two-child limit, I presume William and Kate's third child will receive no state support."