Praise Jesus for this gift, I will pray you are granted a son!
As far as the Will of God goes, I will leave that for a man or Pastor to advise you, as it is not my place.
However, I may be able to offer some information regarding discipline, so that the child is not harmed. Caning/paddling the palms of the hands or soles of the feet is quite a painful experience, making it a very good tool in teaching obedience. As they are extremities, it doesn't seem possible that this could harm the unborn child. You could also try pulling her hair/ I know from experience that this is very uncomfortable! I presume that as she is a Christian woman, she would have long hair, so this should make it much easier to get a good grip.
When all else fails, a good slap to the face will always do, with no damage to your baby
