PewDiePie, whose real name is Felix, and Marzia shared the exciting news on Instagram with a pic of their son saying "Welcome to the family, little Björn".
The YouTuber first announced the news that they were expecting back in February. In the video titled 'We're having a baby!', Felix talked of their excitement of becoming parents.
"It's kind of strange to me, it's entering new territory, but I feel really ready and so does Marzia".
"I have no doubt she'll be an amazing mother," he added saying Marzia was 'the most loving and caring person I know'.
Given that fans of Felix and Marzia have had a front-row seat to the couple's relationship through their YouTube videos, they were quick to share how excited they were about the news.
"this child gonna have the protection of over 100 million people on the internet," wrote one fan with another saying "It’s so wild to think that I’ve been a fan of y’all since 2015 and I’ve gotten to watch y’all grow and settle down to start a family. It’s so awesome and I’m so happy for you guys."