Royal baby! When will Prince William and Kate Middleton have kids?

Apr 29, 2011 at 4:33 p.m. ET

When Prince William (age 28) and Kate Middleton (age 29) have children, they will be in line for the throne as well. But where in line will they fall? And when might the couple start their family? Find out.

William, Kate & a royal baby

Prince William and Kate Middleton were just married, but there is already talk about their potential children. When might they be born? What will their titles be? Where will they fall in line for the throne?

Potential timeline

When might the royal couple start their family? We asked on Twitter, and heard from Kate/Savour that it probably won't be long. "Relatively quickly. She's not 19. (She's not a crone, but as my OB told me -- not as easy to get pg at 33 as it was at 29)," says Kate. We have to agree… and not just because of the Duchess's age.

>> Delaying childbearing: How old is too old?

We looked at the time span between marriage and first child's birth for several members of the royal family and found that, more often than not, babies are born soon afterward.

For instance, William's parents, Prince Charles and Princess Diana, were married on July 29, 1981, and William was born less than a year later on June 21, 1982. Likewise, William's grandparents, Queen Elizabeth II and Prince Philip were married on November 20, 1947, and Charles was born just short of a year later on November 14, 1948.

But not all the royals have such a tight reproductive schedule. Prince Andrew and his ex-wife Sarah Ferguson were married on July 23, 1986 and had their first child on August 8, 1988 -- just over two years later.

>> Duchess Sarah Ferguson: A royal interview

Prince William and Kate Middleton official engagement photo

Meanwhile, Elizabeth The Queen Mother was married for about three years before giving birth to the Queen. And Prince Charles' other siblings, Anne and Edward, were both married for four years before having children.

All things considered, however, it seems extremely likely that Prince William and the Duchess of Cambridge will start a family within the next year or two.

Baby's first title

The first born son of Prince William and his wife will be born with the titles of both "His Royal Highness" and "Prince." Their other children will be Lord or Lady Mountbatten-Windsor.

However, that will change if William's father, Prince Charles, becomes king… though that seems unlikely as of yet.

Succession to the throne

Now, the thing everyone wants to know: Where in the succession line will Prince William and the Duchess's children fall? Right after William, actually. That means that the royals from Prince Harry on will move down the line of succession each time Kate has a baby.

As things stand by law now, the firstborn son of Prince and Princess William will be third in line for the crown behind Prince Charles and Prince William.

Currently, regardless of age, the first-born daughter would fall after her brother or brothers in the line of succession. However, Parliament is seeking to change the law that gives precedence in succession to sons over daughters. Should that be enacted, then Prince William and the Duchess of Cambridge's children will be third in line and so on by birth order, regardless of sex.

>> Boy or girl? Can you influence the sex of your baby?

But first they need to have a baby! When do you think the young Prince and his new bride will have their first new heir to the throne? Any guesses on a boy or a girl? Tell us in the comments below.

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