The advisor just rolls his eyes and returns to work.
820 AD, Spring
1to2
The governor of that city from the south reports that the miners had little success in procuring large amounts of ore; what was mined was used for local industries.
820 AD, Summer
Your wife goes into labor once more.
The child is born dead.
Few days later, you talk with your wife about this.
"No, it is not so difficult for elfs and humans to have children... stillborns do happen, but it is infrequent. I am sorry if I continue to dissappoint you, my liege." You reassure her that it is not her fault.
You and advisor spend the rest of the afternoon pacing about the library - you worrying if perhaps your seed is the cause, and the advisor reading books on procreation of humans with elfs - the amount of such books could be counted on fingers of one hand.
This goes on till late evening.
Suddenly the advisor stops in his tracks as if he was suddenly enlightened.
"MY GOOD LIEGE!" He shouts, unnerved by his potential discovery. "It is not the problem with the differences of anatomy, sire! It's the dwarves!!" You ask him to explain at once.
"Remember, my liege, when you were on the campaign in Augas, we and your Queen Mother wrote to you that the dwarves, who came to visit the tomb in the south, returned to our castle angry and demanding compensation for the tomb's defilement. Alas, we had nothing to give, so they 'cursed' us. Now, both your elven wife and the folk tales say that the dwarves are plague-bearers, friends of death, fungus, darkness, and all that. What if that dwarven curse was to make your family unable to have children? A disease - plague - of seed and womb?"
You can't help but think his logic is a little bit far-fetched, yet on the other hand - the dwarves did put down a curse, and your wife had three still births in three years in a row. This surely must be more than just coincidence.
Next day, during a meeting with courtiers and scholars, you decide to...
A) Ask the priests of the gods of life, fertility, family (and similar departments) to purify and clean your family from the dwarven curse.
B) Send an envoy to the lands far in the west, in hopes of contacting the dwarves and to plead that they lift the curse.
C) Advertise across the Kingdom for services of a traveling wizard; they do show up from time to time, and are known to be able to deal with even most powerful of harmful magic.