Definition: In this task, you will be presented with a text and a pronoun. You should write the name that the pronoun refers to. Position of the pronoun in the text is showed within two "_"s.
Input: William, who became emperor after Frederick's death, shared none of his parent's liberal ideas; his mother viewed him as a ``complete Prussian''. This difference in ideology created a rift between William and his parents, and relations between them were strained throughout their lives. When _his_ father succeeded to the Prussian throne as King William I on 2 January 1861, Frederick became the Crown Prince. <sep>, Pronoun: his

Frederick