Where are they now? Extreme Sisters: Identical twins Anna and Lucy DeCinque and Brittany and Briana Deane Salyers' lives today

Some sister bonds are strong, but these siblings took it to the extreme in the hit reality series Extreme Sisters.

Sisters Anna and Lucy made their mark as "most identical twins in the world", while twins Brittany and Briana surprised the world by marrying identical twin brothers!

Stream episodes of Extreme Sisters for free on 9Now.

Fans were hooked as they followed the ups and downs of the series' most famous sets of twins – along with their unique challenges along the way.

From proposals to pregnancies and everything in between, here's what your favourite Extreme Sisters haven been up to now.

Brittany and Briana Salyer

They say a sister is like a built-in best friend, but identical twin sisters Brittany and Briana took it to a whole other level.

In 2018, their "fairytale" dream came true when they married identical twin brothers Josh and Jeremy – as you guessed it, the quad simultaneously said 'I do' in a joint ceremony.

The couples met at the Twins Day Festival in Twinsburg, Ohio the year before and got engaged in a joint proposal. They have been married for a little over six years now.

"They understand the twin bond because they have it just like we do," said Briana.

In a more spectacular fairytale ending, Briana and Brittany were successful in falling pregnant around the same time.

READ MORE: Brittany and Briana Salyers explain their unique living arrangements with their husbands

The twins then announced their overlapping pregnancies in August 2020.

"Guess what!!?? BOTH couples are pregnant! 🤰🤰," they shared on Instagram. "We are thrilled and grateful to experience overlapping pregnancies and to share this news with you all!

"Our children will not only be cousins, but full genetic siblings and quaternary multiples!"

Brittany and Josh welcomed baby Jett in January 2021, while Briana and her husband Jeremy welcomed another boy – baby Jax – three months later.

All four live under one roof where they raise their collective family.

With Jett and Jax now three years old, the mums pointed out one wild difference between the kids.

"One of our quaternary twin sons got the twin-dads' color hair, and one got the twin-moms'. 💙💙," they captioned a fun family snap.

As they pointed out, one twin has brunette hair just like the dads, while the other has blonde hair like the mums!

Some fans had burning questions for the parents with one follower asking: "Are they technically brothers instead of cousins😮🤔?"

To which the twins replied: "Yes, they are full genetic brothers 🦋🦋."

While another asked: "I understand the cuteness behind but why are you dressing non twins as twins? And how do you support their individuality? 😊❤️."

Briana and Brittany happily replied.

"In our house, everyone understands that each of us has individuality of the soul, whether or not we wear the same shirt as another. 🤍🤍," they began.

"Also, careful not to mistake a 'rare' something for a 'non' something. Jett and Jax are a rare type of genetic sibling set the same age known as 'quaternary twins.' 🍀🍀

"That said, twins don't have a monopoly on matching outfits anyway — can be fun for regular brothers, cousins, besties, buddies, etc.. 👕👕🌟🌟."

Anna and Lucy DeCinque

Aussie twins Anna and Lucy DeCinque introduced themselves as sisters who share everything – including their man.

The sisters met their partner Ben through social media. They are now engaged to their partner Ben who they've shared for the past 11 years.

Fans often wonder however how their relationship works.

"Sharing a boyfriend for us means we get to be together all the time," said Anna prior to their engagement.

With Lucy adding, "There's no jealousy in this relationship. If Ben kisses Anna, he'll kiss me straight after."

READ MORE: Anna and Lucy in tears after realising radical pregnancy plan might not be possible

"They tell me they feel like one person, they want to be treated as one person, then I will," Ben explained.

Ben proposed to the twins in June 2021. He surprised Anna and Lucy at the same place they had their first date – and popped the question with two identical rings of course!

"Anna, you mean the world to me. I want to show you I'm committed to you," Ben said as he got down on one knee. "Lucy, you mean the world to me. I want to show you I'm committed to you as well."

"I want to spend the rest of my life with youse. I love you both."

Despite being engaged, Anna and Lucy revealed the only thing stopping them from getting married is because it's illegal in Australia.

"What's holding us back, is that you can't marry two people," said Ben. "That's our biggest hurdle."

READ MORE: 90 Day Fiancé star Big Ed announces shock split from fiancée following 'impulsive' 24-hour engagement

They've also faced another hurdle – trying to fall pregnant at the exact same time.

According to their doctor, Anna and Lucy had a 1 in 36 chance of naturally falling pregnant at the same time, or at least the same month.

But the odds weren't "good enough" for the pair.

"Having a baby is really important to us, but it will be our biggest challenge, and the biggest fear, because we can't control that," they said.

Today, the twins continue to share regular updates on their social media, including fashion snaps and fun videos.

In May 2024, Anna and Lucy celebrated Ben's birthday. The twins shared the photo with their fiancé writing: "❤️ HAPPY BIRTHDAY OUR LOVE ❤️💙 .

"WE LOVE YOU SO MUCH 💙Your the greatest and we love sharing you! 💛💛🙋‍♀️🙋‍♂️🙋‍♀️."

Another year down, a lifetime to go!

Stream episodes of Extreme Sisters for free on 9Now.

Relive Anna and Lucy's best moments in the videos below: