Contrary to popular belief, Justin Bieber's wife, Hailey, and her father, Alec Baldwin aren't the only Baldwins. Just because they are the most famous (Hailey for being a supermodel and being married to Justin Bieber and Alec for his acting career and having his new family with Hilaria Baldwin) does not mean there aren't more Baldwins in the very big family dynasty.

There are Alec's three brothers and his two sisters. Each of the siblings (except, we think, Jane) all had little Baldwins of their own, making a collective of 23 cousins, including Alec's daughter, Ireland Baldwin, Hailey's cousin.

But which cousins are closest with one another? According to reports, Hailey and her sister Alaia (Hailey's an aunt now, but she's not ready to be a mom) count Ireland as their second sister, so much so that both sisters asked Ireland to be one of their bridesmaids.

Here's the story on the oldest Baldwin's relationship.

Ireland Was There For Hailey On Her Biggest Day

It's always great having cousins that are similar in age to you because not only do they become your extended siblings, but they also become your best friends. You're there for each other in every major life event, no matter what it is.

This is how it's always been for Ireland and Hailey. Even though they are celebrity children and had interesting childhood's they experienced the highs and lows of that lifestyle together.

Related: What Kind Of Relationship Does Hilaria Baldwin Have With Step-Daughter, Ireland?

So, of course, Ireland was going to be over the moon when Hailey and Justin announced their engagement in 2018. In fact, she was so excited that she had to post about it on her Instagram quickly. She posted an adorable snap of herself with Hailey and Alaia as little girls getting into the bath and chose to caption it with lyrics from a certain song by her future cousin-in-law.

"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.

Then, later on, that year, Ireland commented on her cousin and Justin's courthouse wedding. At the time, she said she didn't know what was happening wedding-wise but did stick up for the Biebers when questioned about their PDA.

Related: Ireland Baldwin Powerfully Defends Her Stepmom Hilaria Baldwin Against Haters

"They’re just kissing all over the world," she told Entertainment Tonight. "They’re just kissing and loving and having fun, and I think people take little details and get too caught up in them, and they’re looking too hard. Just let them kiss!"

On the couple getting engaged, Ireland continued to say, "It was meant to be a long time ago, it was just a long time coming. They’re so in love. They really do a lot of good for each other. And that’s the most important thing for me, that he makes her so happy." She concluded that the Biebers are a "respectable couple."

Ireland also told People, "They’re perfect for each other because they’re like the same person. They’re both really sweet. They complement each other. They’re both very loving of each other."

"They’re going through the same struggles, I feel like," she continued. "And they are just helping each other out. As life goes, we all go."

Related: Hilaria Baldwin Shows Support For Hailey Bieber's Struggles With Social Media Pressure

Shortly after, Kim Basinger, Ireland's mom, confirmed that Ireland and Hailey's sister Alaia would be bridesmaids in the wedding. Sure enough, Ireland and the whole Baldwin family came out to support the Biebers at Montage Hotel in Palmetto Bluff, South Carolina, in 2019.

Two years before that, Ireland and Hailey were bridesmaids at Alaia's wedding. Ireland captured some great photos from the time on her Instagram.

Ireland And Hailey Have Matching Tattoos

Way before the cousins bonded at the Bieber's wedding, they bonded by getting matching tattoos, taking their love for each other to the next level.

They reportedly got their family name "Baldwin" tattooed on the inside of their middle fingers, commemorating their love for their family and their bond with each other. The two women came out into the modeling world together and have been there for each other through everything. So it was only fitting.

In 2019, Ireland called Hailey her "little cousin, like my little baby, so I’m so excited to see her growth and her beautiful house that she’s living in. She’s full wife mode now, so I love it."

No word of wedding bells for Ireland just yet, but we know for sure that Hailey and Alaia will both be front and center for it. Their Baldwin sisters for life.

Next: 10 Times Justin Bieber and Hailey Baldwin Were Relationship Goals