There’s another member of the band!
The new addition was born in Nashville, Tennessee, on Tuesday, April 10, at 9:58 p.m. Oliver weighed 9 lbs., 5 oz., upon his arrival.
“Madly in love with our baby boy,” Baylin tells PEOPLE, sharing an exclusive photo of daughter Violet Marlowe, 5, with her new brother. “He has the sweetest spirit and has already made our world a more beautiful place.”
“Oliver Francis Followill has arrived. I’m so in love it hurts,” added Followill.
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Followill and Baylin, a singer-songwriter, married in Brentwood, Tennessee, in November 2009, with Baylin first announcing that she and Followill were expecting baby No. 2 with an adorable Instagram post back in October.
The snapshot featured Violet lying in the sand at the beach next to the words “Big Sister,” spelled out in seashells, with the caption, “Spring 2018.”
The drummer also confirmed the pregnancy with a hilarious photo of his then-expectant wife looking a little worn out on Instagram the day before Thanksgiving.
“No thanksgiving pregnant stress here at all. #turkeyme #babyme #wineme,” Followill captioned the shot of Baylin showing off her baby bump.
The new arrival is the latest addition to the Kings of Leon family — joining cousin Dixie Pearl, the 5½-year-old daughter of Victoria’s Secret Angel Lily Aldridge and Followill’s brother/lead singer Caleb Followill.
Alongside daughter Violet, Baylin stars — while pregnant! — in the music video for the album’s single “In the Summertime,” shared exclusively with PEOPLE.
Next up for Followill — whose latest album with his band, WALLS, was released in 2016 — are a few summer tour dates throughout the U.S., plus three shows in the U.K.