switching from NCP to CP in Dallas County Texas child age 11

[tbradley123]

I am the wife of NCP. His daughter will be 11 in May. She will start middle school in the fall of 2010. We feel as if this is a crutial time to go back to court and honor the daughters request to switch custody from mom to dad.
Question: What are the chances of this happening?
What is the current legal age for a child to choose which parent he or she lives with?
Does the judge listen to the child if reasonalbe request?
Dallas County Texas