Joint legal custody means the parents have equal decision-making abilities. If the parents do not agree on legal custody issues (healthcare, schooling, religion, etc.), then they may need to return to court or mediation to clarify legal custody or to clarify what happens if the parents do not agree. Check your order and make sure it does not already specify what will happen in the event the parents disagree.
A: Since you have joint legal custody pursuant to a court order, then yes, you have equal say in your children’s religious upbringing.
B: You also have equal say in your children’s medical care for the same reason as “A,” however, depending on the exact language of your order, she may have been able to authorize emergency medical care. Sometimes court orders will specify what a parent must do, and give deadlines, to notify the other parent of emergency medical treatment of a child.
C: If she doesn’t agree to therapy for the minor child, you may have to return to court or mediation to have “joint legal custody” clarified.