Napa CASA A Voice for Children is an advocacy group for court appointed children. Advocates are involved with children while in foster care and serve as role models to assure that the children are given the opportunity to excell beyond their circumstances. CASA served 141 children in 2009, which was made possible by ready and willing vollunteers who contributed approximately 6,829 hours of their time. CASA is always welcoming new volunteers.. Napa CASA A Voice for Children has been serving the community since 1996.