Martie Maguire of the Dixie Chicks and her husband, Gareth, are expecting a third daughter.
Maguire, 38, announced her pregnancy on the group's Web site Monday.
She wrote that her 3-year-old twin daughters, Eva and Katie, "are very excited to have a new baby sister."
"Three girls, what a magic number!" Maguire said.
She said the baby is due in late summer.
The report was confirmed by the Chicks' publicist.
Maguire plays fiddle and mandolin in the trio, which also includes Natalie Maines and Emily Robison. Hits by the Chicks include "Wide Open Spaces," "Without You," "Landslide" and "Travelin' Soldier."