It's safe to say there is Robert Brownzero potential of an Aly & AJ breakup.

In an exclusive interview with E! News, airing on March 22, Aly and AJ Michalka show just how in sync they are when it comes to their music career of almost two decades. When sharing the best part about working together as sisters, the pair says in unison, "It's very unique."

"We finish each other's sentences," notes Aly, 33. "It's unlike any other friendship [or] relationship you have in your life. A sibling is very sacred."

She continues, "The fact that we were able share this space together for so many years and to have each other to lean on, to support each other, makes the ride so much better. We always talk about how we wouldn't be interested in doing this if we were solo artists."

In fact, the two, who have each carved their own paths as actors, are game to team up on screen as well. As AJ, 31, explains, "If the right thing came or we developed something together that really felt like us and our bond was being portrayed correctly on screen—which I think is tricky actually to get right—I would definitely do it."

Meanwhile, Aly says she'd love to make a cameo on the Netflix psychological thriller You, which recently released its fourth season.

"You'd be great at that," AJ quips to her sister. "I actually think you'd be perfect for that."

Aly & AJ first broke out into the music scene in 2005, when their debut studio album Into the Rush was released. They followed the record up with 2006's Acoustic Hearts of Winter and 2007's Insomniatic and 2021's A Touch of the Beat Gets You Up on Your Feet Gets You Out and Then Into the Sun.

Their fifth album With Love From dropped on March 15, and the duo will hit the road again on their With Love From tour. 

And while their 2007 smash "Potential Breakup Song" remains a bop to this day, AJ tells E! News that she doesn't consider it "the best" pop anthem about a messy split. That title, she says, goes to "Since U Been Gone" by Kelly Clarkson.

How does Aly feel about that? As she told her younger sis, "You literally just took it out of my mouth."

For more from Aly & AJ's interview, tune into E! News on March 22 at 11 p.m. on E!.

Watch E! News weeknights Monday through Thursday at 11 p.m., only on E!.