We've been bowing down to Beyoncé for years, but it's about time we started showing Solange the same courtesy. Billboard reported that Solange's latest album, A Seat At The Table, just went No. 1 on the Billboard 200 chart. This is a first for the youngest Knowles, who's last album, True, peaked at No. 157 on the same chart in 2012.But this milestone isn't just history-making for Solange. It also means she and Beyoncé are the first sisters to both earn a No. 1 album on the Billboard 200 as solo artists.The only other sibling pairs to achieve this were Michael and Janet Jackson, along with Master P and his brother, Silkk The Shocker. Ironically, Master P is featured on A Seat At The Table, giving pieces of advice in several of the album's interludes.What may be more remarkable is that Solange and Beyoncé have both earned No. 1 albums this year. (Lemonade was Bey's sixth No. 1 album.) They aren't the first siblings to achieve this: Michael and Janet Jackson each topped the charts in 2001 with their respective albums, Invincible and All For You.Of course, Solange and Beyoncé's mom, Tina Lawson, is still very proud of her daughters — with or without the achievement.