1) No; on one other than a court can change the terms of a court order. Your fiance is entitled to the visitation schedule and terms of visitation set out in the court order.2) No, the mother would only have a say IF the order, by its plain terms, gives her a say; and then she'd have to comply with whatever the order says (in terms of the extent of her say, when and why she can refuse to let your fiance see his son, etc.).