The object, also called the addressee, refers to the receiver of the behavior. Objects can be nouns, pronouns, numerals, nominalized adjectives, infinitives, gerunds, object clauses, etc.

So it can be seen that the prepositional phrase to her is not an object. In short, you can think that the clause should be given to her by the prince. It is obviously an object, but now it lacks an object, which/that can be used instead. Finally, according to the structure of attributive clauses, this part is advanced.