Question: Which founding member of the Dixie Chicks first became a lead singer with the Court Yard Hounds?

Context paragraphs:
Amelita (album): Amelita is the second studio album by country band Court Yard Hounds.  It was released in July 2013 under Columbia Records.

The Original Dixie Hick: The Original Dixie Hick is an EP released by country music parodist Cledus T. Judd in late 2003.  Tracks 1, 3, and 4 are all parodies of "Celebrity" by Brad Paisley, while track 2 is a parody of Chris Cagle's "Chicks Dig It".  All four parodies were inspired by the various Dixie Chicks controversies in 2003.  This was also his first album for Koch Entertainment after leaving Monument in 2003.

Emily Robison: Emily Burns Strayer ( Erwin, before Robison; born August 16, 1972) is an American songwriter, singer, multi-instrumentalist, and a founding member of the female country band the Dixie Chicks.  Strayer plays banjo, dobro, guitar, lap steel, bass, mandolin, accordion, and sitar.  Initially in her career with the Dixie Chicks, she limited her singing to harmony with backing vocals, but within her role in the Court Yard Hounds, she has taken on the role of lead vocalist.

Protesting the Dixie Chicks: Protesting the Dixie Chicks is a documentary by American filmmaker Christopher Fleeger, independently released on DVD in 2006.  The film captures the storm of controversy ignited by the remarks of Natalie Maines, lead singer of the Texas pop-country trio the Dixie Chicks.  On March 10, 2003, Natalie Maines, at a concert in London, stated that her group was "ashamed" to be from the same state as President George W. Bush.  In the man-on-the-street style of "Heavy Metal Parking Lot", anonymous fans and protesters are interviewed outside the arenas of the Dixie Chicks 2003 USA tour, while the context of the drama is reenacted with toys and action figures of Natalie Maines, Toby Keith, General John Abizaid, Senator Richard Lugar, Senator John McCain and President George W. Bush.

Travelin' Soldier: "Travelin' Soldier" is a song written and originally recorded by American country music artist Bruce Robison in 1996 and again, in rewritten form, in 1999.  It was later recorded by Ty England on his 1999 album, "Highways & Dance Halls".  The first rendition to be issued as a single was by the Dixie Chicks in December 2002, from their album "Home".  It became the group's sixth and final single to reach No. 1 on "Billboard" "Hot Country Singles & Tracks" (now "Hot Country Songs").  A version of the song featuring Natalie Maines of the Dixie Chicks, Bruce Robison and Robison's wife, Kelly Willis, appears on "KGSR's Broadcasts Vol.  13" album.  Aaron Lewis also recorded a cover of the song as a duet with his daughter Zoe on his 2016 album "Sinner".

Alex Dezen: Alex Dezen (born June 26, 1978) is a solo artist and the lead singer and songwriter for the American rock and roll band The Damnwells.  He is also a multi-platinum selling songwriter.  He holds an MFA degree in English from The University of Iowa's Iowa Writers' Workshop, which he attended from 2008-2010 as a Jeffrey G. and Victoria J. Edwards Fellow.  As a songwriter, he has written and released songs for artists such as Justin Bieber, Matt Hires, Court Yard Hounds, The Veronicas, and others.  He has also written for and worked with a number of additional artist such as The Dixie Chicks, Dave Grohl, Gary Louris of The Jayhawks, Sara Bareilles, Christina Perri, Genevieve Schatz of Company of Thieves, Simple Plan, Jesse & Joy, Bun E. Carlos and many others.  He is currently signed to Warner Chappell Music Publishing.

Court Yard Hounds: Court Yard Hounds is an American country music and folk duo, founded by sisters Martie Maguire and Emily Robison.  They, along with Natalie Maines, make up the Dixie Chicks.  The sisters decided to record a side project under a different name.  Court Yard Hounds, featuring Robison for the first time as lead vocalist, released a debut album for Columbia Records, the same label for which the Dixie Chicks has recorded, on May 4, 2010.  The album debuted at No. 7 on the Billboard 200 chart, initially selling 61,000 copies.  It has sold approximately 825,000 copies in the United States.

Martie Maguire: Martha "Martie" Elenor Erwin (before Maguire; born October 12, 1969) is an American musician who is a founding member of both the female alternative country band, Dixie Chicks and country blue grass duo, Court Yard Hounds.  She won awards in national fiddle championships while still a teenager.  Erwin is accomplished on several other instruments, including the mandolin, viola, double bass and guitar.  She has written and co-written a number of the band's songs, some of which have become chart-topping hits.  She also contributes her skills in vocal harmony and backing vocals, as well as orchestrating string arrangements for the band.

Dixie Chicks: Dixie Chicks are an American country music band which has also crossed over into other genres, including pop and alternative country.  The band is composed of founding members (and sisters) Martie Erwin Maguire and Emily Erwin Robison, and lead singer Natalie Maines.  The band formed in 1990 in Dallas, Texas, and was originally composed of four women performing bluegrass and country music, busking and touring the bluegrass festival circuits and small venues for six years without attracting a major label.  After the departure of one bandmate, the replacement of their lead singer, and a slight change in their repertoire, Dixie Chicks soon achieved commercial success, beginning in 1998 with hit songs "There's Your Trouble" and "Wide Open Spaces".

Court Yard Hounds (album): Court Yard Hounds is the debut studio album by American country duo the Court Yard Hounds, founded as a side project of the Dixie Chicks by sisters Emily Robison and Martie Maguire.  The album was released on May 4, 2010 via Columbia Records.  It was mainly recorded in Maguire's home studio in Austin, and co-produced with Jim Scott (who was also the Grammy-winning sound mixer/engineer on the Dixie Chicks' latest album "Taking the Long Way" and "").

Supporting paragraphs: Court Yard Hounds Emily Robison
Answer: Emily Robison