Ireland Baldwin Sends Love to Cousin Hailey Baldwin Following Justin Bieber Engagement

Ireland and Hailey Baldwin
Vivien Killilea/Getty Images for Karma International

She used a Bieber song lyric to show her excitement!

Ireland Baldwin is thrilled about Hailey Baldwin's engagement news!

The 22-year-old model took to Instagram on Monday to congratulate her cousin on her recent engagement to Justin Bieber. Ireland, the daughter of Alec Baldwin and Kim Basinger, posted a throwback snap of her with her cousins -- Hailey and Alaia -- who are the daughters of Stephen Baldwin.

The three youngsters are taking a bath in the adorable snap, with Hailey grinning for the camera. Additionally, Ireland chose a very apt lyric for the caption -- borrowing from her future cousin-in-law's discography.

"There’s gunna be one less lonely girl ? ... and only one lonely girl left ? my other chicken is soon to be a beautiful bride ♥️. congratulations to the two of you @haileybaldwin @justinbieber," Ireland wrote, quoting the singer's 2009 hit, "One Less Lonely Girl."

Hailey, 21, and Justin, 24, made it official when the singer popped the question in the Bahamas over the weekend.  

"Justin decided to propose to Hailey in front of a group of people in the Bahamas, but had been planning to ask her for a couple weeks now," a source told ET following the engagement. "The ring is gorgeous and Hailey is over the moon with joy. The two can’t stop telling their friends and family how excited they are for their journey together. The two have always had a great bond, and it is stronger now than ever."

The engaged pair dated briefly in 2015 before calling it quits in 2016. Back in June, a source told ET that the two have been "casually dating for roughly a month" and that "things seem to be heating up as the two are spending more and more time together."

Watch the video for more on their relationship timeline:

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