Prince Harry
Meghan Markle's boyfriend Prince Harry, pictured Nov. 20, 2014 in Abu Dhabi, responded to news that his brother and sister-in-law, Prince William and Kate Middleton, were expecting their third child. Getty Images

Good news from Kensington Palace: Kate Middleton and Prince William are expecting their third child. That means Prince Harry is about to be an uncle for the third time and girlfriend Megan Markle could potentially become the baby’s aunt if she were to marry her royal boyfriend.

The baby will be fifth in line to the throne. While monarchy isn’t in Harry’s future, he’s thrilled to welcome another child into his family.

He said he felt, “Fantastic. Great. Very, very happy,” when reporters asked him about Middleton’s pregnancy, according to The Express.

During her first two pregnancies, the Duchess of Cambridge suffered from Hyperemesis gravidarum. It’s a rare condition that causes severe vomiting.

As far as Harry knew, Middleton’s morning sickness wasn’t bad. “I haven't seen her for a while but I think she's OK,” he said.

Kensington Palace announced Monday Kate and William, both 35, are going to be parents for a third time.

“The Duke and Duchess of Cambridge are very pleased to announce that The Duchess of Cambridge is expecting their third child,” the statement said.

The press release also addressed Middleton’s heath condition, which afflicts some pregnant women.

“As with her previous two pregnancies, The Duchess is suffering from Hyperemesis Gravidarum. Her Royal Highness will no longer carry out her planned engagement at the Hornsey Road Children’s Centre in London today,” the statement said. “The Duchess is being cared for at Kensington Palace.”

The couple is already parents to Prince George, 4, and Princess Charlotte, 2. Their oldest child is slated to start school at Thomas’ Battersea in London Thursday. Kate and William will see him off on his first day, according to Entertainment Tonight Online.

Middleton’s sister, Pippa, who married husband James Matthews in May, reportedly wanted to get pregnant the same time as her sister.

“It’s long been a dream for Kate and Pippa to be pregnant at the same time,” an insider told Us Weekly Friday. “To share that would be amazing.”

Pippa would have loved to have been pregnant at the same time as her sister because “Kate has so much knowledge to share. She’s a walking baby encyclopedia at this point,” the source said.

Matthews wants to be a father. “Starting a family is something they’ve spoken about since long before they got married,” said a source about Pipa. “It’s a chat she also had with Kate... Pippa’s always said how great it would be if they were to be expecting together.”

It was just last week that Us Weekly reported Kate and William were ready to have another baby. The Duchess was wanted another baby after she had Charlotte, but juggling a toddler and newborn was a lot of work.

“They promised each other they wouldn’t even think about having another child until they were mentally ready and it felt right,” a source said days before the announcement. “Now is definitely that time. They would love to be pregnant soon.”

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