Sentence:  ‘I didn't <WSD>knock</WSD> you <WSD>up</WSD> when I came in,' Peregrine said. ‘There seemed no point. It was getting light. I just thought I'd leave the note to wake me at seven. And oddly enough I did sleep. Heavily.' 
Meaning of the word marked with <WSD> tags:  To awaken (someone) as by knocking at the door; rouse; call; summon; also, to go door-to-door on election day to persuade a candidate's supporters to go to the polling station and vote. See also (knocker up). (from 17th c.)