Justin and Hailey Bieber are "doing well" following the birth of their first child

A source told People: "They're doing well. They're both overjoyed. The baby is such a miracle. He's adorable and doing well! Hailey's doing well, too. The pregnancy was something that they very much wished and prayed for.

"The day they found out that Hailey was pregnant was the best ever for Justin. He was over the moon with excitement. It was a big celebration for them. Justin's already a great dad."

The 'Baby' hitmaker confirmed the news that he had become a dad with a snap of the newborn's foot held by his mom.

He captioned the picture: "WELCOME HOME. JACK BLUES BIEBER."

The Rhode Skin founder and the 'Sorry' singer announced in early May that they were expecting a child - and revealed Hailey was six months along at the time, making her due date sometime in early August.

Hailey didn't announce their big news until she was six months pregnant as she was able to hide her small bump using "big jackets".

She told W magazine: "I was honestly able to keep it quiet because I stayed small for a long time. I didn't have a belly, really, until I was six months pregnant, which was when I announced it. I was able to wear big jackets and stuff."

Hailey went on to admit she "probably could have" kept the pregnancy a secret all the way through to the birth, but she didn't like keeping such big news quiet.

She added: "I probably could have hid it until the end. But I didn't enjoy the stress of not being able to enjoy my pregnancy outwardly. I felt like I was hiding this big secret, and it didn't feel good. I wanted the freedom to go out and live my life."