The Knowles sisters are getting in formation.

For the first time ever, both Beyoncé and her younger sister Solange have albums on the Billboard 200—and it may also be the first time that any pair of sisters has simultaneously had their own solo chart-topping albums.

Since its release last week, A Seat at the Table has climbed the music charts, becoming No. 2 on the Billboard 200. Music critic and entertainment news journalist Roger Friedman reported Wednesday that this is the first time two sisters have had singles on Billboard at the same time. Alex Vitoulis, Billboard’s associate chart productions manager, could not confirm that this is in fact the case, citing the need for more research, but says it is a “likely” possibility.

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While the two sisters’ music has been very different in the past—Beyoncé has typically produced more pop; Solange is known to be more edgy—the younger Knowles sister’s new album has been compared to Lemonade, the politically charged album Beyoncé released earlier this year.

“It shouldn’t be surprising that two people who grew up in the same household with the same parents who are very, very aware—just like everyone else is—of all of the inequalities and the pain and suffering of our people right now, would create art that reflects that,” Solange said in an interview with The Fader.

While Lemonade surprised some with its explicit political messages, Solange says Beyoncé has always been vocal about racial inequality.

“As far as I’m concerned, she’s always been an activist from the beginning of her career and she’s always been very, very black. My sister has always been a voice for black people and black empowerment,” she told The Fader.