Royal Baby Born Into New Era From Queen Elizabeth II

July 22, 2013— -- intro: Kate Middleton and Prince William welcomed a baby boy today, weighing 8 lbs., 6 oz., the palace announced, to much celebration from royal fans across the world.

The new heir, His Royal Highness Prince of Cambridge, is the third in line to the British throne, after grandfather Prince Charles and father Prince William.

LIVE UPDATES: Welcome Royal Baby

"It'll be the first time since the end of Queen Victoria's reign when we'll have three future monarchs alive ... at the same time as the monarch in residence, the queen," Robert Lacey, author of the book "Majesty," said today on "Good Morning America."

Eighty-seven years separate the newest member of the royal family from the reigning monarch, Queen Elizabeth II, who is "delighted at the news" of the birth, according to the British monarchy's official Twitter account.

Elizabeth has been on the throne for 61 years and much has changed since Elizabeth's birth in 1926, when U.S. postage stamps costs 2 cents, Calvin Coolidge was the U.S. president, and classic children's book "Winnie-the-Pooh" was published. Here's a look back at some of the pop culture milestones from Elizabeth's birth to Prince Wiliam's to the birth today.

Click here for full coverage of the royal baby.

Send your congratulations to Will & Kate! Click here to sign the Royal Baby Book.

quicklist: 1title: Queen Elizabeth IItext: The reigning British monarch, Queen Elizabeth II, has been on the throne 61 years. Born April 21, 1926, Elizabeth, the daughter of the Duke and Duchess of York, came into the world when Calvin Coolidge was in the White House and U.S. postage stamps costs 2 cents each.

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