Pippa Middleton
Pippa Middleton won't know the sex of her baby until after she gives birth. Pictured: Middleton leaves Kensington Palace by car on April 24, 2018 in London, England. The Duke and Duchess of Cambridge's third child, a boy weighing 8lbs 7oz, was born yesterday morning at 11:01. Getty Images/Jack Taylor

Pippa Middleton seems to be following her sister Kate Middleton’s during her first pregnancy.

According to People, Pippa has opted to keep her baby’s gender a secret even from their family and friends. Her husband James Matthews’ brother, Spencer Matthews, recently appeared on “This Morning” to ask about his future niece or nephew.

Host Ruth Langsford told Spencer, “And your brother is about to become a dad as well a little bit after you with Pippa Middleton. So, they do know if they’re having a boy or a girl?”

“They don’t. They’re extremely private and honestly, we know nothing,” Spencer replied.

The publication noted that the Duchess of Cambridge never disclosed her three children’s identity until after they were born. In April, just days before Kate gave birth to Prince Louis, a source told E! News, that she and Prince William also didn’t know that they will have a boy.

“William and Kate don’t know the sex of their baby, so they’re rather looking forward to finding out. It’s very difficult to be totally prepared when you don’t know if it’s going to a boy or a girl,” the source said.

According to BBC, the royal couple also didn’t know that they were having a boy during Kate’s pregnancy with Prince George. Princess Charlotte’s sex also came as a surprise to them.

However, not knowing the sex of the unborn child is not part of a royal protocol. Princess Diana, for instance, knew she was having boys during both of her pregnancies. Earlier this year, former royal butler Paul Burrell revealed that Princess Diana told him that she was pregnant with a boy before Prince Harry was born.

“She said, ‘It’s a boy, it’s our secret.’ And I kept that a secret because I couldn’t even tell the Queen, I couldn’t tell my wife, I couldn’t tell anyone. That was our secret until Harry was born,” he said (via Hello!).