Britney Spears is a proud aunt again!
The superstar, 36, congratulated her little sister Jamie Lynn Spears Thursday afternoon on her brand new baby girl.
“I could not be more excited to welcome baby Ivey to this world. Congrats to @jamielynnspears and the whole family – I love you all so much!!!” the singer — who is mom to sons Sean Preston, 12, and Jayden James, 11 — wrote on Twitter.
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Jamie Lynn — who wed Jamie Watson in 2014 — welcomed Ivey Joan (she also shares 9½-year-old daughter Maddie Briann with ex Casey Aldridge) on Wednesday, April 11, at 10:02 a.m., her rep confirmed to PEOPLE exclusively.
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Ivey was born in Covington, Louisiana, weighing 7 lbs., 8 oz. and measured 19½ inches in length.
“We are beyond excited to welcome this beautiful baby girl to our family!” Jamie Lynn, 27, told PEOPLE, adding of Ivey’s name, “Her middle name, Joan, is to honor my Aunt Sandra, who passed away 10 years ago from ovarian cancer. She was the most graceful woman I’ve ever known.”