Inside Justin Bieber and Hailey Baldwin's Engagement — 'They Know Each Other Very Well': Source

From “Boyfriend” to fiancé!

Justin Bieber and Hailey Baldwin are engaged, and a source says the whirlwind proposal makes sense for the young pair.

“It’s kind of a surprise, but kind of not. Justin has been extremely happy these past few weeks,” says the source. “He has known Hailey for a long time. This might seem sudden, but they know each other very well.”

As TMZ first reported, Bieber, 24, popped the question to Baldwin, 21, Saturday night over dinner in the Bahamas.

RELATED: Justin Bieber and Hailey Baldwin Are Engaged! He’s ‘Extremely Happy,’ Says Source

Hailey Baldwin and Justin Bieber
Hailey Baldwin and Justin Bieber

Both of Bieber’s parents appeared to hint at the engagement Sunday on social media.

“@justinbieber Proud is an understatement! Excited for the next chapter!” dad Jeremy Bieber captioned an Instagram post. Meanwhile, mom Pattie Mallette tweeted: “Love Love Love Love Love Love Love.”

@justinbieber Proud is an understatement! Excited for the next chapter!

A post shared by Jeremy Bieber (@jeremybieber) on Jul 8, 2018 at 8:31am PDT

The “Sorry” singer and model-turned-Drop the Mic host previously dated before a messy split in 2016. After calling it quits,“we went through a long period of time when we weren’t friends,” Baldwin recently told U.K. newspaper The Times.

RELATED: From a Whirlwind Engagement to Hailey Baldwin to His Status with Selena Gomez: Inside Justin Bieber’s Lady Squad

Hailey Baldwin and Justin Bieber
Hailey Baldwin and Justin Bieber

“Justin and I were friends for a long time,” she said in the interview. “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 didn’t speak for quite some time and there was a lot of weirdness that went on … we’ve moved past that.”

RELATED VIDEO: Justin Bieber and Hailey Baldwin Hit Washington State for Church and a Hot Tub Session

The couple rekindled their romance this summer, fueling rumors they had reconciled as they packed on PDA during trips to Miami, New York City and the Hamptons.

Hailey Baldwin and Justin Bieber
Hailey Baldwin and Justin Bieber

In June, an insider told PEOPLE that Bieber and Baldwin have bonded over their faith and shared church parish over the years.

“They’re very close because of Hillsong,” the insider said. “She definitely cares about him. They also have a long history together.”