Hailey Bieber and Justin Bieber have a baby, baby, oh. 

The Rhode Beauty founder and "Sorry" singer welcomed their first child together, the couple shared on Instagram Aug. 23. 

"WELCOME HOME," Justin wrote alongside a photo of the little one's foot while introducing baby Jack Blues Bieber.

And Hailey celebrated the birth of baby Jack as well, resharing Justin's post to her Instagram Story. 

And the couple's friends and family were just as thrilled about the news, with Kylie Jenner commenting under Justin's post, "I can’t handle this little foot JACK BLUES."

Meanwhile, the "Peaches" singer's longtime pal Alfredo Flores echoed the Kylie Cosmetics founder's sentiments, writing, "Congratulations!!! i’m sooooooooooo excited!!! love y’all down."

Baby Bieber's arrival comes three months after Justin and Hailey first announced they were expecting. In posts shared to their respective Instagram accounts May 9, the couple revealed not only that Hailey was pregnant, but also glimpses of their sweet vow renewal in Hawaii. 

In the footage, Hailey, 27, donned a white lace Saint Laurent gown that accentuated her bump, while Justin, 30, wore an Atlanta Braves baseball hat with a black jacket and pants. In one photo, Justin holds on to Hailey's bump from behind as the couple share an embrace. 

Since tying the knot in 2018, the couple have shared insight into their plans to expand their family. After all, Hailey teased to GQ that she was "looking forward" to motherhood last October—but not without some fears.

"I literally cry about this all the time!" Hailey admitted in a May interview with The Sunday Times. "I want kids so bad but I get scared. It's enough that people say things about my husband or my friends. I can't imagine having to confront people saying things about a child."

Ultimately, she noted, "We can only do the best we can to raise them," adding, "As long as they feel loved and safe."

Meanwhile, Justin has been family planning for years. 

"I'd love to have myself a little tribe," Justin explained to Ellen Degeneres on her daytime talk show in 2020. "I am going to have as many as Hailey is wishing to push out—it's her body and whatever she wants to do—I think she wants to have a few."

Keep reading to see Justin and Hailey's full road to parenthood. 

Justin and Hailey take a selfie backstage at the Today show in 2009. She is a month shy of 12, he is 15.

Hailey and her dad Stephen Baldwin join Justin at the premiere of his biopic Never Say Never in New York City. Hailey is 14 and Justin is a month shy of 17.

Hailey celebrates her 18th birthday with Justin and other friends, such as Kylie Jenner and Kendall Jenner. No romance rumors yet.

Hailey and Justin appear together in Instagram pics, sparking romance rumors.

"I've known him since I was so young—since I was like 13—and we've just been good friends over the years," Hailey tells E! News at the time. "We have just stayed close and there's nothing more to it than that."

"People are crazy. I'm super single and this is my good friend u would know otherwise," Justin says, alongside a photo of him and Hailey sitting in a car.

The two are spotted out dining in New York and New Jersey and also hang out at his residence.

Justin celebrates his 21st birthday with Hailey and other friends in the Caribbean.

Selena, who at this point had dated Justin on and off until 2014, shocks fans by liking a video he posts that shows him hula-hooping with Hailey at Target. Friendly exes?

Justin and Hailey spark engagement rumors thanks to a bogus news story, which also spurred the hashtag #CongratsJustinandHailey.

The two are spotted walking together in Beverly Hills.

Justin and Hailey get cozy while celebrating the holiday in Anguilla.

Justin and Hailey don't look too happy in paparazzi photos from their New Year's trip to the Caribbean.

The two share a passionate kiss on a night out.

A source tells E! News that Justin and Hailey's relationship is "more of a just a fling," adding, "They have a lot of fun together but don't know what will happen now. They aren't thinking too much about it and are just having fun."

The two reunite in San Francisco for Super Bowl 50 Weekend.

"They are not an exclusive couple even though Hailey has made it clear that's what she wants from Bieber," a source tells E! News. "They spent the night together Saturday."

"All of Bieber's friends like Hailey and would like to see them together," the source adds. "They are dating. They both had a great time this weekend with each other."

"Hailey made me get corn rows like an absolute douche bag, these will be off tomorrow trust me Danny," Justin says, showing off a new look during their vacation.

Meanwhile, a source tells E! News, "Hailey and Justin have a very tight relationship. They both are very close with each other's families and care very deeply about each other. Hailey's family has been there and supported Justin through his transition so Justin has a strong respect for them."

"He loves Hailey as a friend and considers her one of his best friends," the source adds. "They both also have a strong attraction towards each other and this trip they have been having fun with their families, but also had some alone time. Hailey and Justin like to party and let loose and this romantic connection has always been there."

Justin tells GQ magazine that Hailey is "someone I really love," adding, "We spend a lot of time together."

"We are not an exclusive couple. He's about to go on tour," Hailey tells E! News about Justin after his GQ article comes out. "Relationships at this age are already complicated, but I don't really like to talk about it because it's between me and him."

"Hailey is not dating anyone at this time, just hanging out with her friends and working," a source tells E! News. "Bieber and Hailey are still close friends, but he is on tour and extremely busy now, so they have not seen each other that much. Bieber and Hailey love each other but have a good understanding where they both stand at the moment."

"I don't want attention out of dating somebody," Hailey tells Marie Claire. "Texts started coming through, crazy phone calls...it's hard to date somebody in this industry. You have to have really thick skin and be very strong. You have to focus on the person and nothing else."

The two grab some java as they head to the airport in NYC.

Justin and Selena rekindle their romance.

E! News learns Hailey is dating the singer.

The two call it quits over their romance again.

Justin and Hailey attend the same church service together.

Hailey and the singer make their joint red carpet debut at the prestigious celebrity event, fueling romance rumors. They post photos of each other on Instagram.

Hailey tells the Times UK that she and Shawn "hang out and he's super-lovely and a very, very nice young gentleman," adding, "But I am single."

She also says, "Justin and I were friends for a long time. I met him when I was really young and he was one of my best friends. Everybody knows that at a certain point in time that turned into something else, but that just happens when you're 18, 19. It was what it was. We went through a long period of time when we weren't friends. We didn't speak for quite some time and there was a lot of weirdness that went on. We've moved past that."

He tells E! News, "I am single. The Met Ball was such an incredible experience for me. It was just overwhelming in the most incredible way. I was so lucky for my first time going there to be able to go with someone like Hailey because she's such a vet and I really admire people like her because of how outgoing she is in such an overwhelming experience."

Justin and Hailey reunite in Miami, sparking romance rumors again.

Justin and Hailey pack on the PDA in New York City, which is captured on video.

"I don't know if they're dating or not," Shawn Mendes tells Canada's eTalk, adding, "I love them both. They're both really awesome people."

For the latest breaking news updates, click here to download the E! News App