Kate Middleton has been pregnant for about six weeks with Prince William's first baby, the celebrity gossip magazine In Touch reported.

In Touch cited a royal source, who has correctly revealed other secrets, including their honeymoon location and the queen’s wedding gift, as saying that Kate is definitely pregnant.

“Since before they even got married, it’s been made clear to William and Kate that having children should be their number-one priority,” the royal source told the magazine.

Without doubt, the royal couple couldn’t be more relieved, for the source also revealed that Queen Elizabeth II has given them hints many times that she wants a great-grandchild -- and an heir to the throne.

Although Middleton is currently only in the first trimester of the pregnancy, it is said that the couple is already preparing for nurseries in each of their three residences.

Kate and William are also picking names for the possible future king or queen -- their first-born child will be eligible to inherit the throne regardless of its sex.

“They want something traditional,” the source told the magazine. “Edward, Philip, and Michael are likely choices for a boy ... Alice or Rose for a girl.”

The insider also said the royal couple hopes the baby is a girl.

“He’s very much his mother’s son, and he also knows that his father, Prince Charles, would like a granddaughter,” the insider said, explaining that Kate agrees. “She’s happiest when William is happy,” the source said.

Start the slideshow to see for yourself whether Kate is pregnant or not.