He had checked in the library-marriages could be annulled, but that was not something that could be easily or quietly done, even by the crown prince. Only the King himself could directly put his queen aside. The heir had no such powers unless infidelity was involved. Barring that, Elia would have to be forced into the silent sisters or killed to end the marriage. Both would result in pushback from her family. There was also the fact that any trueborn children from that marriage would not lose their place in the line of inheritance, according to a law implemented by Jaehaerys I. Putting aside their mother would create great resentment down the line.