Legal Question in Family Law in California

No. The child's wishes is only one factor in the court's determination of what custody order would be in the child's best interests.

The child's wishes is taken into consideration. So, yes, her wishes do in fact count. A lot will depend on how she represents in mediation. If you proceed, then you should have a qualified family law attorney represent you. Good luck!

A threshold question that must be addressed is how old is te child. If she is a mature teenager, the court can consider the child's desires. If the child is young, it's unlikely that the child's request will be weighed into the parenting equation but it could be justification to assess if the family needs counseling to address issues giving rise to the child's request to change custody.