Kate Middleton and Prince William want another girl in their brood.

According to Caitlyn Hitt, a journalist for Daily Mail, the Duke and Duchess of Cambridge are reportedly considering to have another child because they want to give their only daughter, Princess Charlotte, a sister. At the time, Prince William and Middleton are parents to three royal children – 4-year-old Prince George, 3-year-old Princess Charlotte and 2-month-old Prince Louis.

According to the betting odds, Prince William and Middleton might have another child after Prince Louis. Many believe that the royal couple will still add another baby to their brood.

"We have already taken bets on Kate and William having a fourth baby and the odds suggest Prince Louis won’t be their last," John Hill of Coral said (via Express). "Prince Louis is fifth in line to the throne, therefore he is a big price to ever become King."

Also, an insider told Richard Kay that Prince William wants to follow his grandmother, Queen Elizabeth II, and have four children. Middleton reportedly feels the same.

"He would love to emulate his grandmother and have four children and he would be very happy if it was another girl," one of Prince William's pals told the writer. "Having Charlotte was an improving effect on George who was a bit of a tearaway in the early days, so he knows the benefit a second daughter might bring."

While the Duke and Duchess of Cambridge are likely to have another child, Prince Harry and Markle are not into having many children. While in Dublin, a woman ran into the Duke and Duchess of Sussex and encouraged them to get started in expanding their family.

"My husband also has red hair and he gave me five children — when are you and Meghan going to get going," Elaine Adam-Stewart asked Prince Harry. "He laughed and said 'Five children? Too many.'"

Many are hoping that Prince Harry and Markle will announce their first baby before the year ends. At the time, chances are slim that the new royal is expecting. Markle was seen sipping a glass of champagne in one event during their official royal visit in Ireland.